31 August 2021

Mosman Oil and Gas Limited

("Mosman" or the "Company")

Spud of Winters-2 well

Mosman Oil and Gas Limited (AIM: MSMN) the oil exploration, development, and production company, advises that the drilling of the Winters-2 well in East Texas is expected to commence as soon as the contracted drilling rig is available.

Mosman (via its 100% owned subsidiary Nadsoilco LLC "Nadsoilco") has assumed Operatorship and it is ready to spud the Winters-2 well as a development well targeting the Wilcox formation. Nadsoilco will have a 28.62% working interest in this well.

Mosman acquired an interest in the Winters lease as part of its purchase of Nadsoilco. The Winters lease is held by production with circa 969 bbls of oil sold in the last 12 months from the Winters-1 well.

The rig contractor has advised of the current challenges to secure rig crew due to the ongoing effects of the COVID-19 pandemic in the USA. As soon as a firm drill date has been confirmed, further announcements will be made in regard to the commencement of drilling.

Mosman continues to work on its other East Texas projects, including Greater Stanley, Falcon, Galaxie and Cinnabar, as well as workovers at Stanley. Important technical work is also progressing at the Amadeus Basin exploration assets in Australia.

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