UPDATE 1-Russia's Vekselberg may sue RUSAL in oligarch row
* RUSAL's shares slide in Hong Kong
* Fight escalates with lawsuit threatened
* RUSAL says its claims are accurate
* Board member says there's no crisis at RUSAL
By Polina Devitt and Megan Davies
MOSCOW, March 14 (Reuters) - Russian billionaire Viktor Vekselberg is considering suing RUSAL over accusations that he failed to fulfil his duties as its chairman, intensifying a battle with rival oligarch Oleg Deripaska at the world's largest aluminium producer.
A lawsuit between two of Russia's richest men would risk becoming a spectacle to rival a legal battle between two other oligarchs, Boris Berezovsky and Roman Abramovich, which gave an unflattering insight into the Russian business world. It could also be deeply embarrassing for RUSAL.
The two billionaires have been fighting over Deripaska's ambition of turning RUSAL into a global-scale metals and mining business by merging it with Norilsk Nickel, the world's top nickel and palladium miner. Continued...