RUSAL, whose chief executive and main owner is rival Russian oligarch Oleg Deripaska, said Vekselberg - who had blamed management of plunging the company into a "deep crisis" - had jumped before he was pushed for not attending board meetings.

Barry Cheung Chun-Yuen, who joined RUSAL's board as an independent director in 2010, chairs the Hong Kong Mercantile Exchange.

Cheung told Reuters on Wednesday that the chairman should be "someone strong" with independence, especially as the current chief executive is the largest shareholder. This, he said, would improve RUSAL's corporate governance.

"(RUSAL) is not in deep crisis. Its operations are normal, but it faces challenges because of falling aluminum prices," Cheung said in Hong Kong earlier this week. "However, the debt level is much lower than when it was listed."

The shareholder dispute revolves around Deripaska's refusal over the past year to sell a strategic stake in Arctic miner Norilsk Nickel (GMKN.MM) over the past year in a deal that could have cleared RUSAL's $11 billion debt burden at a stroke.

RUSAL declined to comment.

(Reporting By Polina Devitt; writing by Megan Davies, Editing by Douglas Busvine)

• A Permanent Economic Emergency