(Reuters) - Former BP (>> BP plc) chief executive John Browne will be vacating his spot on the board of investment company Riverstone Energy (>> Riverstone Energy Ltd) to focus on work for a Russian-backed energy venture, Sky News reported.

The resignation of Browne, who joined Riverstone in 2007, is expected to come as early as Tuesday, Sky News said.

In addition to quitting Riverstone's board, Browne has also relinquished the chairmanship of Cuadrilla Resources, a shale gas firm, the website said.

The resignation was expected as Browne in February announced his appointment as executive chairman of L1 Energy, a $10 billion oil and gas venture backed by Russian billionaire Mikhail Fridman and his partner German Khan.

Riverstone and Browne did not immediately respond to a Reuters request for comment.

(Reporting by Ismail Shakil in Bengaluru; Editing by Christian Plumb)

Stocks treated in this article : BP plc, Riverstone Energy Ltd