28 September 2018

Mosman Oil and Gas Limited

("Mosman" or the "Company")

Arkoma Project Update

Mosman Oil and Gas Limited (AIM: MSMN) the oil exploration, development and production company, announces an update on its Arkoma Stacked Pay Project in Oklahoma.

Mosman Directors recently met with the Operator, Inland Operating Company ("Inland") and the other owner Blackstone Oil and Gas Inc (Blackstone). Discussions continue with Inland and Blackstone on how to optimise the production. However, given the more attractive alternatives for capital investment Mosman has not exercised the Second Option and this option will now lapse.

Market Abuse Regulation (MAR) Disclosure

Certain information contained in this announcement would have been deemed inside information for the purposes of Article 7 of Regulation (EU) No 596/2014 until the release of this announcement.

Enquiries:

Updates on the Company's activities are regularly posted on its website www.mosmanoilandgas.com