Consent Solicitation – Important Update

NOT FOR RELEASE, PUBLICATION OR DISTRIBUTION (A) IN OR INTO OR TO ANY PERSON LOCATED OR RESIDENT IN THE UNITED STATES, ITS TERRITORIES AND POSSESSIONS (INCLUDING PUERTO RICO, THE U.S. VIRGIN ISLANDS, GUAM, AMERICAN SAMOA, WAKE ISLAND AND THE NORTHERN MARIANA ISLANDS, ANY STATE OF THE UNITED STATES AND THE DISTRICT OF COLUMBIA) (THE "UNITED STATES" OR THE "U.S.") OR TO ANY "U.S. PERSON" AS DEFINED IN REGULATION S UNDER THE UNITED STATES SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"), OTHER THAN (I) A "QUALIFIED INSTITUTIONAL BUYER" AS DEFINED IN RULE 144A UNDER THE SECURITIES ACT ("RULE 144A") THAT HOLDS OR IS ACTING FOR THE ACCOUNT OF ANOTHER QUALIFIED INSTITUTIONAL BUYER THAT HOLDS NOTES OR (II) AN "ACCREDITED INVESTOR" WITHIN THE MEANING OF RULE 501(A)(1), (2), (3), (7), (8), (9), (12) OR (13) OF REGULATION D UNDER THE SECURITIES ACT THAT HOLDS OR IS ACTING FOR THE ACCOUNT OF ANOTHER ACCREDITED INVESTOR THAT HOLDS NOTES OR (B) IN OR INTO ANY OTHER JURISDICTION WHERE IT IS UNLAWFUL TO RELEASE, PUBLISH OR DISTRIBUTE THIS ANNOUNCEMENT.

THIS ANNOUNCEMENT CONTAINS INSIDE INFORMATION

Nostrum Oil & Gas Finance B.V.

(incorporated under the laws of the Netherlands)

CONSENT SOLICITATION - IMPORTANT UPDATE

On 8 September 2026, Nostrum Oil & Gas Finance B.V. (the "Issuer") announced invitations to Eligible Holders of the following Notes to approve, as a resolution in writing, or to the extent that is not achieved, at a meeting of the holders of the Notes (the "Meeting"), the relevant resolutions (the "Extraordinary Resolutions") set out in the Notice of Meeting delivered to the Clearing System for communication to Direct Participants (the "Consent Solicitation").

The Consent Solicitation Memorandum dated 8 September 2026 prepared by the Issuer (the "Consent Solicitation Memorandum") and the Notice of Meeting are available to Eligible Holders from GLAS Trust Company LLC (the "Information and Tabulation Agent") as set out below.

Capitalised terms used in this announcement but not defined have the meanings given to them in the Consent Solicitation Memorandum.

This announcement shall be incorporated into, and form part of, the Consent Solicitation Memorandum and shall therefore constitute Information Incorporated by Reference.

Important Update Regarding U.S. Sanctions

The Issuer hereby notifies holders of the Notes (the "Noteholders") of the following developments relating to the Consent Solicitation:

On 14 September 2026, the Office of Foreign Assets Control ("OFAC") of the U.S. Department of the Treasury designated VTB Bank Public Joint Stock Company ("VTB Bank") on the Specially Designated Nationals and Blocked Persons List pursuant to the Iran-related Executive Order 13902 ("E.O. 13902"). As a result of this designation, a VTB Bank affiliated entity, which is a Noteholder whose interests are held in the Holding Period Trust, is now blocked pursuant to E.O. 13902 (in addition to being blocked under the Russia-related Executive Order 14024 and Executive Order 13662).

While the Issuer had previously obtained a specific license from OFAC (License No. MUL-2022-929317-3, issued by OFAC on 29 May 2026, the "Current License") authorising U.S. persons to engage in certain transactions that involve persons whose property and interests in property are blocked pursuant to the Russian Harmful Foreign Activities Sanctions Regulations and/or the Ukraine-/Russia-Related Sanctions Regulations, the Current License does not authorise such transactions that involve persons blocked pursuant to the Iran-related E.O. 13902.

As a result of the designation of VTB Bank pursuant to E.O. 13902, the Issuer is no longer able to rely on the Current License to consummate the Consent Solicitation contemplated under the Consent Solicitation Memorandum.

Steps Being Taken by the Issuer

The Issuer and its advisers are working as a matter of urgency to seek an amendment to the Current License that would authorise U.S. person transactions that would have been authorized, to the extent authorisation is required, under the Current License but for the most recent designation by OFAC of VTB Bank pursuant to the Iran-related E.O. 13902 on 14 September 2026.

The Issuer has submitted a request to OFAC asking that the amended license be issued by no later than 29 September 2026, being shortly prior to the date of the Meeting at which Noteholders voting on the Extraordinary Resolutions is scheduled to take place on 1 October 2026.

Action Requested of Holders of Notes

The Issuer proposes that holders of the Notes continue to submit their Consent Instructions to the Information and Tabulation Agent in accordance with the procedures set out in the Consent Solicitation Memorandum. However, the Issuer hereby notifies holders of the Notes that, for OFAC sanctions compliance reasons, it has taken steps to ensure that the Extraordinary Resolutions shall not be approved as resolutions in writing unless and until the Issuer has obtained the necessary amended OFAC sanctions license that will allow it to consummate the Consent Solicitation.

The Issuer will provide a further announcement in due course regarding the status of the amended OFAC license, the Consent Solicitation and the Meeting.

Further Information

Requests for copies of this announcement, the Consent Solicitation Memorandum or related documents and questions should be directed to:

INFORMATION AND TABULATION AGENT

GLAS Trust Company LLC

3 Second Street, Suite 203
Jersey City, New Jersey 07311
United States

Email: [email protected]

Dated: 22 September 2026

LEI: 213800SGF6UKA42KSB50

Further Information

For further information please visit www.nostrumoilandgas.com

Further Enquiries

Nostrum Oil & Gas PLC                                          

Yelena Zhuravleva, CFO

[email protected]

TEAM LEWIS                                                                                        

Galyna Kulachek

+ 44 (0) 20 7802 2664

[email protected]

About Nostrum Oil & Gas

Nostrum Oil & Gas PLC (the ultimate parent company of the Issuer) 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 announcement are forward-looking. Forward-looking statements include statements regarding the intent, belief and current expectations of the Group or its officers with respect to various matters. When used in this announcement, 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 Group or any other entity, and shareholders of the Group are cautioned not to place undue reliance on the forward-looking statements. Save as required by the relevant listing rules and applicable law, the Group does not undertake to update or change any forward-looking statements to reflect events occurring after the date of this announcement.