Rosneft may buy BP's stake in TNK-BP

Rosneft, the Russian state oil giant, has emerged as a suitor for BP's stake in the troubled TNK-BP joint venture, which it put up for sale after "unsolicited indications of interest" from unnamed parties.

Although Rosneft's chief executive, Igor Sechin, denied making an approach, his group is understood to be among those to have informally indicated an interest in BP's 50 per cent holding.

BP said it was obliged to "pursue a potential sale" to comply with the requirement to maximise shareholder value. The energy giant would be glad to extricate itself from dealings with AAR, the consortium of four Russian billionaires which owns the other half of TNK-BP. Their fraught, nine-year relationship has included court cases and claims of harassment by Bob Dudley, then head of TNK-BP and now BP's chief executive, which forced his exit from Russia in 2008.

The market welcomed BP's decision, sending its shares up by as much as 4 per cent at one point.

However, analysts were unsure how much its stake might fetch. Although BP and Rosneft almost bought out AAR's holding for $32bn (£20.9bn) last year, that deal was never completed and TNK-BP's value has since tumbled, meaning BP's share could be worth closer to $20bn.

Last year, AAR went to court to block a tie-up between BP and Rosneft on the basis that the TNK-BP shareholder agreement entitled them to first refusal on any opportunities in Russia.

On Monday, Mikhail Fridman, the AAR consortium leader, quit as chief executive in a move seen as preparing the ground for a Russian attempt to seize control of the venture.

Mr Fridman told Russia's Kommersant newspaper that the joint venture was paralysed and could only prosper if one of the two partners took full control.

The prospect of state-owned Rosneft buying BP's stake in TNK-BP would likely raise fears within AAR that the venture could effectively be assumed by the Russian government. As a result, AAR may eventually consider selling its own stake in TNK-BP to Rosneft, giving BP the Russian partner it wanted, but failed to get, last year.

Alternatively, BP sells the stake, thereby exiting a venture which has brought it much strife.