7 March 2022

Mosman Oil and Gas Limited

("Mosman" or the "Company")

Winters-2 First Gas Production

Mosman Oil and Gas Limited (AIM: MSMN) the oil exploration, development, and production company, announces initial production from the Winters-2 well in East Texas.

The initial flow rate is circa 545 thousand cubic feet per day (mcfpd), which is circa 105 barrels of oil equivalent per day (boepd). This well and equipment will be monitored, and the initial rate may be adjusted in due course. Mosman has c23% working interest ('WI') in Winters-2.

The new production will add significantly to the average daily gross production which was 164 boepd in the December 2021 quarter.

Onsite focus has now moved to establishing production from Stanley-4 (Mosman 36.5% WI). Production rates from that well will be announced shortly.

John W Barr, Chairman, said: "Mosman is pleased to see that following completion of gas infrastructure, enabling gas production from the Winters and Stanley leases,  this initial flow rate is an excellent starting point and we look forward to continuing to build our production base."

Market Abuse Regulation (MAR) Disclosure

The information contained within this announcement is deemed by the Company to constitute

inside information as stipulated under the Market Abuse Regulations (EU) No. 596/2014 ('MAR') which has been incorporated into UK law by the European Union (Withdrawal) Act 2018. Upon the publication of this announcement via Regulatory Information Service ('RIS'), this inside is now considered to be in the public domain.

Enquiries:

Updates on the Company's activities are regularly posted on its website:

www.mosmanoilandgas.com