Interim Results 2024

Prior to publication, the information contained within this announcement was deemed by the Company to constitute inside information as stipulated under the UK Market Abuse Regulation. With the publication of this announcement, this information is now considered to be in the public domain.

Deltic Energy Plc / Index: AIM / Epic: DELT / Sector: Natural Resources

26 September 2024

Deltic Energy Plc ("Deltic" or "the Company")

Interim Results

Deltic Energy Plc, the AIM-quoted natural resources investing company with a high impact exploration and appraisal portfolio focused on the Southern and Central North Sea, is pleased to announce its interim results for the six months ended 30 June 2024.

Highlights

• Farmed down a 25% interest in Licence P2437 including the Selene prospect to Dana Petroleum (E&P)
  Limited ("Dana"), resulting in Deltic now being fully carried for the estimated success case cost of the well.
• The Shell operated Selene exploration well, targeting Gross P50 Prospective Resources of 318 BCF in the UK Southern North Sea, was spudded on 28 July. Operations are expected to take approximately 90 days from spud and the Company will update the market as appropriate.
• Deltic accepted two out of the four licences provisionally awarded by the North Sea Transition Authority ("NSTA") in the UK's 33rd Offshore Licensing Round. Both licences contain attractive low risk, low cost, infrastructure led exploration opportunities with nominal capital commitments in Phase A of the licences.
• On 10 June Deltic notified its Joint Venture ("JV") partners on Licence P2252, containing the Pensacola discovery, of the Company's intention to withdraw from the licence.
• Deltic has now reached agreement with the JV partners on Licence P2252, limiting the Company's liabilities associated with withdrawal from licence P2252 to £1.9 million with payment of circa 50% of this amount deferred for a period of 24 months.

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• Cash position of £3.7 million at 30 June 2024 (31 December 2023: £5.6 million)

Graham Swindells, CEO, commented:

"There is no doubt that the first half of the year has been one of the most challenging periods for the Company since its inception, with highly publicised fiscal and political pressures impacting companies operating across the UK's domestic oil and gas sector. Despite these unprecedented headwinds, the Company continues to make significant commercial and operational progress, which has resulted in a farm-down to Dana which limits our potential cost exposure to the high impact Selene exploration well which is currently being drilled, as well as the award of two new UK licences located close to key production hubs in the Central and Southern North Sea.

Despite our necessary withdrawal from Pensacola, Deltic remains in a strong position to extract significant value for shareholders from our existing UK asset portfolio over the coming months and years. While limiting our cost exposure to UK exploration, the Company remains committed to continuing its exploration-led growth strategy and is actively evaluating investment opportunities in other jurisdictions where we can leverage our team's core strengths and where a more supportive approach to the future oil and gas exploration and development prevails."

Looking back at over 40 years of my career in this sector, of which about half was spent in the North Sea, each year would have been a story of good news and bad news. An explorationist will tend to dwell on the good news and optimism but a good explorationist will reflect and learn from the less good news.

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The outcome for Pensacola was undoubtedly a disappointment. We worked hard to interrogate the data and find an opportunity overlooked by others. The discovery was a cause for celebration. To lose it subsequently was a blow to the team. When we brought Pensacola forward for drilling, reservoir quality was the main uncertainty; an exploration risk. Fortunately, reservoir quality appeared good. Instead, timing of the next phase of investment got caught up in the politics of an election campaign where energy and the future of the North Sea sector were treated as a political football and our involvement in Pensacola ended for a different reason.

But we are prepared for this. Our business model was built to cope with some prospects inevitably falling by the wayside for various reasons. This was why we created a conveyor belt of opportunities; a portfolio of exploration opportunities which allow us to continue with our programme of discovering the oil and gas our country needs for decades, according to the Committee of Climate Change and our new Prime Minister.

We should be optimistic that the new government will eventually recognise the importance of our domestic natural resources for jobs, for treasury receipts, for energy security and for emissions, compared with imported supplies.

And this leads us to the good news: a jack-up drilling rig is currently conducting drilling operations at our Selene prospect. Selene is another prospect the Deltic team uncovered and successfully brought in Shell and Dana, not only to share in the resources of the opportunity but to cover our costs of technical work and exploration drilling. The whole team is happy to be back to the part of exploration where we open the box and find out what's in it.

This is exploration in a mature basin. You examine, you discover, and you move on.

Mark Lappin

Chairman

25 September 2024

CEO Statement

I reflect on the year to date with mixed emotions, ranging from the hugely disappointing forced withdrawal from the Pensacola licence to the positive progress on Selene with a successful farm-out to Dana in February, the spudding of the high impact Selene exploration well in July and the award of new licences with significant potential as a result of success in the 33rdoffshore licensing round. All this has been achieved against the highly publicised backdrop of continual degradation of the UK fiscal regime, as it pertains to exploration and production operations on the UK Continental Shelf (UKCS), and negative sentiment driven by policy announcements from a Labour government in waiting in the run-up to the general election in July.

Despite this the Company has always believed in the strength of its portfolio to deliver value for shareholders and through selective acceptance of 33rdRound awards we have moved our UK portfolio away from higher

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risk greenfield exploration to a more infrastructure-led asset base which we believe will be relevant and valuable under any future regime, especially as access to further new licences is likely to be highly restricted.

Over the next year the focus will be on limiting our cost exposure, through farm-down or deferral of planned work programmes on our existing assets, while looking to extract value from our investment in the UK to date. The team has demonstrated its ability to identify high quality opportunities, execute the technical work that much larger organisations respect and to attract investment from these larger oil and gas companies to move projects forward into drilling and hopefully beyond. These core skillsets can continue to be leveraged as we look to deliver value both from our existing portfolio but also as we look forwards towards future opportunities and expansion of the portfolio.

Pensacola

Despite an exhaustive process, increasing political and fiscal uncertainty exacerbated by the timing of the general election meant that Deltic was ultimately unable to secure a farm-out or an alternative funding solution which would allow the Company to fulfil its future commitments with respect to the Pensacola appraisal well which was due to be drilled in the second half of this year. Consequently, Deltic had to withdraw from the licence prior to being required to formally undertake further drilling obligations in early June.

In the course of this process, the Company examined a wide variety of funding solutions which included potential industry partners, including existing partners, via traditional farm-out or asset sale, the equity capital markets, strategic investors and debt providers. However, paralysis amongst potential farm in partners unable to make investment decisions in such a politically toxic environment, coupled with erosion of confidence amongst the investor community, resulted in the Company being unable to find a solution to continue with Pensacola.

The Company subsequently notified the partners of Licence P2252 of the Company's intention to withdraw from the licence. An agreement with the JV partners to limit Deltic's trailing liabilities for costs incurred prior to withdrawal under the Joint Operating Agreement (JOA) has been reached along with a deferred repayment agreement which is positive for Deltic's short term working capital position. Further details of this agreement are set out below.

While the withdrawal from Pensacola has been extremely disappointing, this draws a line under what has been a very difficult period for Deltic and its shareholders. Now this has been settled we can look forward to the results of the ongoing Selene well operations in the coming months.

Selene - Farm-out and Drilling

Excellent progress was made on Selene throughout the course of the first half of 2024. The farm out to Dana was completed and the rig contract was entered in February for the Valaris 123, a heavy duty jackup rig. The Valaris rig was mobilised in July with drilling operations commencing on 28 July 2024. Well operations are

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underway and are planned to take approximately 90 days after which the rig will be demobilised from the Selene well location.

The farm-out to Dana formed part of the strategy to mitigate Deltic's cost exposure to the upcoming well while bringing in a further high-quality partner. As a result of this transaction, and when combined with the existing Shell carry, Deltic retains a 25% interest in Licence P2437 and has no exposure to the success case drilling costs up to a gross cap of $49M, which is in excess of the success case well cost estimates.

The Selene exploration well is the first exploration well drilled on the UKCS in 2024 and is an equally important milestone for Deltic. The Selene prospect is a high impact, infrastructure-led exploration opportunity which, in the case of exploration success, we believe should remain commercially viable under any envisaged future fiscal regime.

In contrast to Pensacola, the 318 BCF (Gross P50 Prospective Resources) Selene prospect is a simple Leman Sandstone structure in an established, well understood play and located close to existing production infrastructure. In a successful outcome, Selene is not expected to require further appraisal prior to field development planning commencing and could therefore be brought into production relatively quickly following discovery given the proximity of existing infrastructure.

We note the proposed acquisition of a package of Shell and ExxonMobil's South North Sea assets, which includes the Selene prospect, by Viaro Energy ("Viaro"). Based on released information we would expect this transaction to complete in mid-2025 with Viaro assuming operatorship of the Selene asset and the proposed evacuation route via Barque, Clipper and the Bacton Gas Terminal onshore Norfolk. It is encouraging that Viaro continue to take a positive counter-cyclical approach to the UK exploration and production sector and we believe that they will inherit the same significant commercial drivers that should support a rapid development of Selene in the event of exploration success, that initially attracted Shell to the asset in the first place.

We look forward to successful drilling and updating the market in relation to the well.

Other licences - Syros (P2542)

The farm-out process on the Syros prospect located in the Central North Sea, in close proximity to the production infrastructure associated with the Montrose and Arbroath fields, generated an encouraging level of interest from potential farminees interested in joining Deltic on this asset. However, as we have seen across the industry, planned farm-in discussions have been suspended pending a review of the expected update to the UK's taxation regime which will be presented in the October budget.

Given the impact that previous alterations to the Energy Profits Levy, the General Election earlier in the year and the ongoing uncertainty associated with the October budget, have had on corporate decision making, Deltic has requested a 12 month extension to Phase A of the licence from 1 December 2024 to 1 December

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2025 from the NSTA. If this extension is granted, it will allow potential partners sufficient time to assess the impacts of any changes to the EPL and re-engage with Deltic in relation to farming into this asset.

Licence Awards

In the first half of 2024, Deltic continued to add to its portfolio of licences through further success in the UK's 33rd Offshore Licensing Round.

Dewar (P2646)

On 1 February 2024, we were pleased to announce the award of the Dewar licence which has previously been licenced and matured by Deltic. Dewar is considered a low-risk prospect in the Forties Sandstone, located close to existing and proposed new infrastructure associated with the redevelopment of the Murlach Field (formerly known as Skua) with P50 Prospective Resources estimated at 21 mmboe.

The work programme associated with the initial phase of the licence is restricted to upgrading the seismic data sets held by the Company at relatively low cost and is focussed on providing greater confidence around prospect volumetrics and risk before embarking on a farm out process.

Blackadder (P2672)

We were subsequently pleased to confirm the formal award of Licence P2672 which lies immediately to the west of the West Sole gas field in the Southern North Sea. The licence contains the Pharos and Teviot discoveries with Pharos and Blackadder now considered to be one single structure with P50 Prospective Resources of 165 BCF. The location and nature of the Blackadder project provide it with many similarities to Selene, where the reworking of legacy datasets has identified a potential missed pay opportunity of material scale. Blackadder's location, in close proximity to existing infrastructure, should enhance its value in a basin where new licences are likely to become increasingly scarce.

Over the coming year, we will progress our work on the legacy data in preparation for farm-out, in anticipation of drilling an appraisal well on Blackadder.

These awards are a direct result of the hard work that our technical team put into the application process and the licences accepted have been selected by Deltic to have the best potential to be progressed and create additional drilling opportunities in the future.

Outlook

The first half of 2024 has seen the outlook for the UK's oil and gas industry become increasingly uncertain, further heightened by the recent election and the proposals put forward by the Labour government. This uncertainty remains following the Government's policy update on 29 July 2024, which increases and extends

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the EPL, removes the uplift on allowances while leaving a decision on other allowances until the next budget on 30 October 2024. Deltic continues to engage in and support industry lobbying efforts and it is hoped that the new Government's first budget will provide an element of clarity and much needed stability if the UK oil and gas industry is to avoid an accelerated decline.

Despite these challenges, we are nonetheless pleased to have added to the Company's portfolio of licences with further success in the latest licensing round with the award of the Dewar and Blackadder licences and we are particularly excited to have started drilling at Selene with our partners Shell and Dana.

The fact that we are in the second half of the year and Selene is the first exploration well to be drilled in the UKCS clearly demonstrates the impact that political and fiscal instability has had on levels of activity and investment. Therefore, until further clarity exists Deltic intends to limit further investment in its UK portfolio (other than Selene) and will look to pursue opportunities overseas in jurisdictions that are more favourable and supportive of the oil and gas industry. Our team has significant international experience and believes that it can bring this to bear on such opportunities.

Although our industry faces ongoing uncertainty, we look forward to successful operations at Selene, and continue to believe exploration on the UKCS has a hugely important role to play in supporting the provision of energy security, jobs within the energy sector and the ability to offset higher carbon intensity imported energy.

I would like to take this opportunity to thank the entire Deltic team for their continued hard work and dedication throughout the year to date.

Graham Swindells

Chief Executive Officer

25 September 2024

Operating Review

Pensacola - Licence P2252 and P2558

As previously announced, Deltic has withdrawn from licence P2252, which contains the Pensacola discovery, due to an inability to secure a further farm-out or alternative funding structures given the perceived political threats to the industry and ongoing fiscal uncertainty in the run-up to the UK general election on 4 July. The process of transferring Deltic's equity share in Licence P2252 to the remaining partners Shell U.K. Ltd and ONE- Dyas is ongoing.

The Shell-Deltic JV has completed the technical review of potential follow-on opportunities in the Zechstein on adjacent licence P2558. While exploration potential remains within the licence area, no immediately viable drilling opportunity has been identified by the JV and the NSTA has been notified of the JV's intention not to proceed beyond Phase A of the licence. The licence will be allowed to expire on 30 November 2024.

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Selene - Licence P2437

The Selene prospect is a 4-way dip closed structure in the Leman Sandstone in the heart of the play fairway and close to offtake infrastructure which is located some 20km to the south of the well location. Deltic has a 25% non-operated interest in the P2437 licence and estimates the Selene structure to contain gross P50 Prospective Resources of 318 BCF (P90 to P10 range of 132 to 580 BCF) and a geological chance of success (GCoS) of 69%.

As previously announced, the Valaris 123 rig was mobilised to the Selene site from the Central North Sea on the 21stJuly. Drilling operations commenced on the 28thJuly with well operations expected to take approximately 90 days to complete. The well is being operated by Shell U.K. Ltd.

The Selene opportunity with its material recoverable volumes, low development CAPEX and proximity to existing offshore production infrastructure has what we consider to be an almost unique combination of characteristics in the Southern North Sea which, in the case of exploration success, we believe makes it remain relevant and commercially viable under almost any future fiscal regime.

We will update the market in due course upon completion of drilling operations.

Blackadder - Licence P2672

The Blackadder prospect was provisionally awarded to Deltic on a 100% basis in Tranche 3 of the 33rd Offshore Licensing Round and formal licence documentation was received and executed in early July.

The licence is located immediately to the west of the West Sole gas field and covers blocks 47/5e, 47/10c and 48/6c and contains the Pharos and Teviot discoveries. Deltic's preliminary evaluation, completed as part of the application process, has resulted in an updated understanding of the structural setting, which suggests that the Pharos discovery and the Blackadder prospect are in fact a single Leman Sandstone structure.

Deltic's preliminary evaluation of the combined structure estimates P50 Prospective Resources of 165 BCF (P90 to P10 range of 66 to 293 BCF) with a GCoS of 65%. These estimates will be reviewed and updated as part of the Phase A work programme associated with the licence.

Blackadder is highly analogous to the Selene opportunity both in terms of its geological setting but also in relation to access to offtake infrastructure which should speed up commercialisation timelines in the event of a discovery.

The Phase A work programme commitments are focussed on the reprocessing of legacy 3D seismic data to improve reservoir imaging and refine the structural model in order to further de-risk the Blackadder structure. Total expenditure associated with the Phase A work programme is estimated at less than £200,000.

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Syros - Licence P2542

The Syros licence is held 100% by Deltic and contains the Syros prospect, which is hosted in the Jurassic aged Fulmar Sandstone, a prolific producing reservoir on the western flank of the Montrose-Arbroath High in the Central North Sea.

The prospect is mapped as simple rotated fault block on modern high quality 3D and is estimated to contain a light gassy oil with P50 Prospective Resources of 24.5mmboe (P90 to P10 range of 13.7 to 39.7mmboe) with a GCoS of 58%. While a number of potential development options exist, the most likely would be a short subsea tieback to the existing production infrastructure located on the Montrose-Arbroath High.

Following a number of management team changes and corporate ownership changes in licences around the Syros prospect, the Company saw an uptick in interest in the ongoing Syros farm-out process prior to the announcement of the general election in May 2024. The ongoing political and fiscal uncertainty is proving extremely unhelpful in drawing these discussions to a conclusion and Deltic has requested a 12 month extension to Phase A of the licence from the NSTA.

Licence P2542 will expire on the 30 November 2024 unless either a farm-down can be secured or an extension to Phase A is granted by the NSTA.

Dewar - Licence P2646

Licence P2646 containing the Dewar prospect was awarded to Deltic on a 100% basis in Tranche 2 of the 33rdOffshore Licensing Round. Dewar is a low-risk prospect in the Forties Sandstone, located close to existing and proposed new infrastructure associated with the redevelopment of the Murlach Field (formerly known as Skua) in the CNS.

Deltic currently estimates the Dewar prospect to contain P50 Prospective Resources of 20.8 mmboe (P90 to P10 range of 10 to 38.2 mmboe) with a GCoS of 36%.

The Phase A work programme associated with the licence is restricted to upgrading the key seismic data sets held by the Company at relatively low cost and is focussed on providing greater confidence around prospect volumetrics and risk. The early stage work will also look in detail at the alternative development and export options that were not available last time the company had an interest in this particular opportunity.

Portfolio and Resource Summary

The Company's current licence portfolio and prospect inventory, as of the end July 2024, is summarised below:

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Southern North Sea - Prospective Resources

1Operated by Shell

Central North Sea - Prospective Resources

Andrew Nunn

Chief Operating Officer

25 September 2024

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