The world's biggest aluminium producer Rusal on Friday named the head of the Hong Kong Mercantile Exchange as new chairman after a bitter public struggle between its Russian oligarch shareholders.

Rusal said that Barry Cheung, who is also chairman of Hong Kong's Urban Renewal Authority, would become chairman of Rusal's board of directors after the shock resignation this week of Russian magnate Viktor Vekselberg.

Vekselberg said hugely-indebted Rusal was facing "a deep crisis" under the operational control of its chief executive and fellow Russian magnate Oleg Deripaska who owns a 47.4-percent stake in the company.

Making no attempt to keep the dispute private, Rusal had accused Vekselberg of skipping board meetings and said he would have been ousted anyway if he had not resigned first. Vekselberg controls 15.8 percent of Rusal.

Cheung, a non-executive Rusal director since 2009, "will have an expanded role in providing leadership and guidance for Rusal's growth strategy, especially in China and the rest of Asia," Rusal said in a statement.

Deripaska meanwhile said he was "thrilled" at the appointment and Cheung said he would seek to increase the number of independent directors at the company. Rusal is listed on the Hong Kong stock exchange.

Rusal was left with massive debts by the 2008-2009 financial crisis and has been under increasing pressure from its shareholders to part with its 25-percent stake in the world's largest nickel producer Norilsk.

Among the other main shareholders, fellow tycoon Mikhail Prokhorov controls a 17.0-percent share while the Russian arm of the Swiss-based mining company Glencore owns 8.75 percent.