United Company RusAl chief executive Oleg Deripaska accused Michael Cherney, who is suing him for $4.3 billion, of making mysterious payments to politicians including Israel Deputy Prime Minister Avigdor Liberman.

The claims emerged at a London court hearing where Cherney's lawyer said accusations made by Deripaska's legal team were a "distraction." The hearing indicates that Deripaska will fight Cherney's suit by painting him as someone who used his connections to extract protection payments from businessmen.

Claims that Cherney made "large, unexplained payments to politicians," including Liberman and a Bulgarian prime minister, "don't have any relationship to the facts of the case," said his attorney, Mark Howard.

Cherney, now living in exile in Israel, filed a London lawsuit in 2006 claiming that he was Deripaska's partner and is owed a stake in RusAl. The trial, scheduled to begin in April, follows the three-month, $6.8 billion courtroom battle between Russian oligarchs Boris Berezovsky and Roman Abramovich.

"They say Mr. Cherney was the mastermind of the imposition of krysha payments" on businessmen, Howard said, referring to a Russian word for protection. Cherney's lawyers were seeking to prevent some of the claims being used in the trial.

Calls and e-mails to Liberman's office weren't returned. Deripaska's spokeswoman in London, Idil Oyman, declined to immediately comment. Cherney's spokeswoman Georgie Gibbs didn't immediately respond to a request for comment.

Judge Andrew Smith said the April trial might be delayed until the parties were better prepared.