Rosneft, led by executive chairman Igor Sechin, has taken the clear lead in the industry following its takeover of Russo-British oil venture TNK-BP last year.

Unlike arch-rival Gazprom, Rosneft has been eager to expand its co-operation with foreign companies, both in Russian offshore blocks in the Arctic and in tight oil onshore acreage. The company is also working to eat into Gazprom’s domestic market share, planning to more than double its gas production by 2020.