Oligarchs war at Oleg Deripaska's metal giant Management at Rusal hit back with a statement in which they said Mr Vekselberg had failed to perform his duties and was about to be removed anyway. He had not attended a board meeting since February 2011, the company said. "Mr Vekselberg had failed to perform his functions as a public company board chairman over the past 12 months," Rusal said. In this respect, the decision of Mr Vekselberg to resign as chairman of the board pre-empted the anticipated consideration of this matter by the board. It is understood that Mr Vekselberg, who has a 15.8pc stake in Rusal, had approached the rest of the board to offer them the option to buy his shares, as they have first refusal. However they declined to pay the price he wanted, a factor thought to have played a part in his departure. The news of Mr Vekselberg's resignation came a week before the group releases fourth-quarter results in which it is expected to post net income of about $300m, about a tenth of the profit it reported at the start of last year. Rusal, which produces about 10pc of the world's aluminium output, has been hit by a steep fall in the metal price, against a backdrop of spiralling costs and overcapacity in the sector. Mikhail Prokhorov, who recently came third in Russia's presidential elections, controls a 17pc stake in the company, while Glencore, the FTSE 100 commodity trading giant, owns 8.75pc. Mr Vekselberg is also one of the group of billionaires who jointly control the Russian venture TNK-BP Holding together with oil major BP.