Russian oligarch Oleg Deripaska will step down as president of his two biggest companies En+ Group and UC Rusal, Russian daily Kommersant reports, citing sources close to the companies' shareholders. The decision is connected to a corporate showdown between some of Russia’s biggest oligarchs for control of metals giant Norilsk Nickel.

Maxim Sokov, EN+’s CEO, and Rusal CEO Vladislav Solovyov will step up to lead the respective companies at a board meeting slated for the end of this week. Deripaska will retain his seat as a non-executive director on the boards of both companies. The tycoon said that he will switch all his attention to GAZ, the iconic automotive company that he also owns. Deripaska was the president of En+ from 2013, and UC Rusal from 2014.

Two sources cited by Kommersant say that Deripaska intends to withdraw from the presidency of UC Rusal against the background of changes in the company's shareholder structure. In 2017 aluminium producer SUAL shareholders Viktor Vekselberg and Leonard Blavatnik increased their stake in Rusal to 20.5%, Mikhail Prokhorov's Onexim reduced his to 6%, and Swiss trader Glencore plans to exchange 8.75% of Rusal for 11% of En+.

Standing behind the changes is the growing corporate dispute between Deripaska and fellow oligarchs Roman Abramovich and his partner Alexander Abramov, who control steel miner Evraz, together with Vladimir Potanin, a blue-blooded oligarch from the Yeltsin-era, over control of the metals giant Norilsk Nickel.

Potanin’s holding company Interros owns 30.4% of Norilsk Nickel’s shares and is trying to buy 6.5% owned by Abramovich and Abramov. Last week Rusal sought a London court injunction against the proposed share sale.

Norilsk was subject to a bitter boardroom struggle for control between Potanin and Deripaska until the Kremlin imposed a peace settlement on them in 2012 that included Abramovich taking the 6% stake as peacemaker.

Crispian Investments Limited, the Abramovich and Abramov investment vehicle, received a proposal from one of the structures of Interros called Bonico Holdings Co Ltd to buy 6.313mn Norilsk Nickel shares that Crispian holds for $234 per share and $23.4 for the ADRs, UC Rusal said . In a letter, Crispian also offered to provide UC Rusal and another structure of Interros – Whiteleave Holdings – the "right of first refusal" after the purchase. Crispian holds 4.2% of Norilsk according to Vedomosti, and all in all Abramovich and Abramov's structures  own a total of 6.3% of the company.

Afraid the corporate war between the two tycoons is about to break out again, shares in Norilsk tumbled on February 16 more than 8% as the news of the court battle broke.

Deripaska’s decision to step down from his two leading companies is also seen as a prophylactic move to protect him from possible US sanctions that could hurt the share price of both companies, which are listed in London and Hong Kong respectively.

Deripaska has been particularly scandal ridden recently. He has been a member of the inner Kremlin circles since his marriage to Viktor Yumashev’s daughter, the former chief of staff to Boris Yeltsin and key member of the so-called Family clan that ran Russia in the 1990s. Last week anti-corruption blogger and opposition activist Alexei Navalny claimed in an expose that Deripaska had hosted Deputy Prime Minister Sergey Prikhodko and call girls on his yacht, and had conspired to influence the US presidential elections with the use of dirt supplied by US political consultant Paul Manafort, who worked for Deripaska at the time.

Sources at the two companies said that Deripaska's exit from management was an attempt to insulate the companies from any possible fall-out from politically charged attacks on the shareholder. EN+ is considering an SPO after the March Russian presidential elections that is supposed to raise $1bn for the company.

"When you have the right of final signature and the need to conduct numerous negotiations, increased attention due to the list can be problematic," Kommersant cited a source in the company as saying.