The UK Government proposes to revoke North Sea petroleum licences owned by DEA UK, unless LettrOne, owned by Russian oligarch Mikhail Fridman, offloads its stake.

Fridman’s investment fund LetterOne acquired 12 oil and gas fields from RWE’s oil and gas unit DEA in March.

The UK Department of Energy & Climate Change (DECC) has, however, raised concerns about the possible future sanctions imposed on LetterOne. It said such sanctions may result in serious health and safety and environmental risks.

RWE went ahead with the deal despite the concerns raised by the UK Government. The Ukrainian crisis has bought the deal under increased investigation with sanctions imposed on some Russian businesses.

"The gas fields bought by LetterOne account for approximately 3% to 5% of UK supplies."

The gas fields bought by LetterOne account for approximately 3% to 5% of UK supplies.

DECC said in its latest announcement: "The Secretary of State Ed Davey has notified Dea UK and LetterOne that he proposes to revoke Dea UK’s North Sea petroleum licences unless LetterOne arranges for a further change of control of the Dea UK gas fields in the North Sea."

LetterOne has up to six months to make a change in ownership.

The statement said the decision was taken following a review of all relevant information as well as obtaining cross-government views.