Tony Hayward, the former head of BP who stepped down after the Gulf of Mexico oil spill catastrophe, is leaving his post on the board of its Russian joint venture TNK-BP, the company said Monday.

Hayward, who came under huge criticism for his role in the clean-up of the oil spill, took on the role at TNK-BP as a BP-appointed director in July 2010, when Robert Dudley took over as head of the British giant.

Hayward "informed the board that he would step down from the TNK-BP board of directors in order to pursue other opportunities," TNK-BP said in a statement.

"The board accepted his resignation, while at the same time recognising the significant contribution Mr Hayward has made to TNK-BP's development," it added.

Hayward become notorious in the oil spill fiasco for declaring "I would like my life back" and then being spotted sailing off the south coast of England at the height of the crisis.

TNK-BP is owned 50 percent by BP and 50 percent by a group of Russian billionaires. Its operation of huge oil fields in Siberia makes it one of the British firm's crown jewels and accounts for a quarter of its total production.

But it has also been hit by the bitter boardroom power struggle that followed BP's failed bid to strike a lucrative Arctic oil project with Russia's state held firm Rosneft, a deal that TNK-BP also coveted.

The BP-Rosneft deal collapsed when the Russian shareholders in TNK-BP -- who include banker Mikhail Fridman -- protested that it violated their own shareholder agreement with BP.

BP has since come under pressure from a multi-billion-dollar lawsuit filed by a minority investor in the TNK-BP Holding company and in the past month was hit by raids on its Moscow offices by bailiffs linked to the case.

The British firm's troubles were also discussed during this month's visit to Moscow by Prime Minister David Cameron, who raised the issue with both his Russian counterpart Vladimir Putin and President Dmitry Medvedev.

Notably, TNK-BP did not specify who would replace the BP appointee to the board.

"A replacement for Mr Hayward will be appointed to the board in due course, at which point the company will make a separate announcement," the company statement said.

Fridman, currently serving as TNK-BP's acting chief executive, said he was "immensely grateful to Tony Hayward ... (and) confident that his future endeavors will be successful and fulfilling."

TNK-BP suffered a hugely damaging dispute in 2008 that saw Dudley, then its chief executive, accused of damaging the Russian shareholders' interests and then effectively forced to leave Russia.

That dispute was patched up after Dudley's departure and the shareholders agreed to appoint Maxim Barsky TNK-BP chief executive effective from January 1, 2011.

However amid rumours Barsky could be on his way out of the company and headed for a different assignment, he has still to take up his post, leaving Fridman leading TNK-BP in an acting capacity.

TNK said tersely only that the board "did not discuss any senior management appointments in TNK-BP" at its meeting.