The information contained within this announcement is deemed by the Company to constitute inside information as stipulated under the retained EU law version of the Market Abuse Regulations (EU) No. 596/2014 ("MAR"). Upon the publication of this announcement via Regulatory Information Service ("RIS"), this inside information is now considered to be in the public domain. If you have any queries on this, then please contact Steve Boldy, the Chief Executive Officer of the Company (responsible for arranging release of this announcement).

28 June 2023

Lansdowne Oil & Gas plc

("Lansdowne" or the "Company")

Barryroe Lease Undertaking Application

Initiation of Arbitration Process under the Energy Charter Treaty ("ECT")

Further to the Company's announcement of 22 May 2023 that the Company was formalising the engagement with external legal counsel to pursue legal proceedings for the purpose of protecting its investment in the Barryroe Project, Lansdowne is pleased to announce that its legal advisors, Ashurst LLP, have submitted a letter to Ireland giving notice pursuant to Article 26(2)(c) of the Energy Charter Treaty, requiring Ireland to participate in discussions with a view to settling the dispute within three months of the date of such notice. Receipt of this letter has been acknowledged.

Further updates will be made as appropriate, along with more information on the claims sought by Lansdowne in this matter.

For further information please contact:

Notes to editors:

About Lansdowne

Lansdowne Oil & Gas (LOGP.LN) is a North Celtic Sea focused, oil and gas exploration and appraisal company quoted on the AIM market and head quartered in Dublin.

For more information on Lansdowne, please refer to www.lansdowneoilandgas.com.