Notification of interest payments on the Notes.

NOT FOR RELEASE, PUBLICATION OR DISTRIBUTION, IN WHOLE OR IN PART, IN OR INTO OR TO ANY PERSON LOCATED OR RESIDENT IN ANY JURISDICTION WHERE TO DO SO WOULD CONSTITUTE A VIOLATION OF THE RELEVANT LAWS OF THAT JURISDICTION

THIS ANNOUNCEMENT CONTAINS INSIDE INFORMATION

London and the Netherlands, 11 June 2026

Notification of interest payments on the Notes

Nostrum Oil & Gas Finance B.V. (the "Issuer"), a wholly-owned subsidiary of Nostrum Oil & Gas PLC (the "Parent"), was initially required by 30 June 2025 and 31 December 2025 to have paid accrued interest in accordance with the terms and conditions of the Issuer's outstanding 5.00% senior secured notes due 2026 (ISIN: USN64884AF16; US66978CAF95) (the "SSNs") and 1.00%/13.00% senior unsecured notes due 2026 (ISIN: USN64884AE41; US66978CAD48) (the "SUNs" and together with the SSNs, the "Notes").

Capitalised terms used herein but not otherwise defined shall have the meaning given to such terms in the terms and conditions of the Notes set out in the Trust Deeds relating to the Notes each dated 9 February 2023 (as amended and/or supplemented from time to time).

As previously announced by the Parent, these interest payments were not paid due to payment administration issues preventing the Issuer from making payments on the Notes through the clearing systems whilst an additional regulatory licence related to sanctioned noteholders was sought by the Parent and the Issuer.

The Parent is pleased to announce that the applicable regulatory licence was obtained on 29 May 2026. Accordingly, the Issuer is required under the terms and conditions of the Notes (as amended through the Issuer's 2025 consent solicitation exercise) to make these interest payments within 10 business days, which is on or before 12 June 2026.

The Issuer intends to initiate the following payments with value date 12 June 2026:

(i)         with respect to the SSNs, U.S.$6,109,300.00, (being U.S.$25 per U.S.$1000 in principal amount) in cash interest with respect to the Interest Period ending on (but excluding) 30 June 2025 and U.S.$6,109,300.00, (being U.S.$25 per U.S.$1000 in principal amount) in cash interest with respect to the Interest Period ending on (but excluding) 31 December 2025, in each case to be distributed via DTC in accordance with its usual operating procedures; and

(ii)         with respect to the SUNs:

(a)        U.S.$2,142,155.85, (being U.S.$5 per U.S.$1000 in principal amount) in cash interest with respect to the Interest Period ending on (but excluding) 30 June 2025 and U.S.$2,281,395.99, (being U.S.$5 per U.S.$1000 in principal amount) in cash interest with respect to the Interest Period ending on (but excluding) 31 December 2025, in each case to be distributed via DTC in accordance with its usual operating procedures; and

(b)        U.S.$27,848,027.00, (being U.S.$65 per U.S.$1000 in principal amount) in PIK Interest with respect to the Interest Period ending on (but excluding) 30 June 2025 and U.S.$29,658,149.00, (being U.S.$65 per U.S.$1000 in principal amount) in PIK Interest with respect to the Interest Period ending on (but excluding) 31 December 2025, in each case to be applied by the Principal Paying Agent increasing the principal amount of the outstanding applicable Global Certificates of the Notes by annotating such increased amount on the schedule attached to such Global Certificates and also reflected in the electronic records of DTC in accordance with its usual operating procedures.

The record date for such payments shall be 11 June 2026.

The Parent thanks holders of the Notes for their support and participation surrounding these third party issues which affected these interest payments on the Notes.

LEI: 2138007VWEP4MM3J8B29

Further information

For further information please visit www.nostrumoilandgas.com

Further enquiries

Nostrum Oil & Gas PLC                                                

Yelena Zhuravleva, CFO

ir@nog.co.uk                                                                                                     

TEAM LEWIS                                                                                         

Galyna Kulachek

+ 44 (0) 20 7802 2664

nostrum@teamlewis.com

About Nostrum Oil & Gas

Nostrum Oil & Gas PLC is an independent energy company with gas processing infrastructure and an export hub in north-west Kazakhstan. Its shares are listed on the London Stock Exchange (ticker symbol: NOG). The principal producing asset of Nostrum Oil & Gas PLC is the Chinarevskoye field which is operated by its wholly-owned subsidiary Zhaikmunai LLP, which is the sole holder of the subsoil use rights with respect to the development of the Chinarevskoye field. The Company also owns an 80% interest in Positiv Invest LLP, which holds the subsoil use rights for the "Kamenskoe" and "Kamensko-Teplovsko-Tokarevskoe" areas in the West Kazakhstan region (the Stepnoy Leopard fields).

Forward-Looking Statements

Some of the statements in this document are forward-looking. Forward-looking statements include statements regarding the intent, belief and current expectations of the Company or its officers with respect to various matters. When used in this document, the words "expects", "believes", "anticipates", "plans", "may", "will", "should" and similar expressions, and the negatives thereof, are intended to identify forward-looking statements. Such statements are not promises nor guarantees and are subject to risks and uncertainties that could cause actual outcomes to differ materially from those suggested by any such statements.

No part of this announcement constitutes, or shall be taken to constitute, an invitation or inducement to invest in the Company or any other entity, and shareholders of the Company are cautioned not to place undue reliance on the forward-looking statements. Save as required by the relevant listing rules and applicable law, the Company does not undertake to update or change any forward-looking statements to reflect events occurring after the date of this announcement.