The World Chess Federation (FIDE) says its Swiss bank accounts have been closed after its president was accused of facilitating transactions on behalf of the Syrian government.
Russian millionaire Kirsan Ilyumzhinov was added to a US Treasury Department sanctions list in 2015 for his alleged dealings with the Assad government.
He denies wrongdoing, and stepped back from FIDE to try to resolve the issue.
But FIDE says Swiss bank UBS closed its accounts as he is still sanctioned.
“After more than two years of Kirsan Ilyumzhinow’s [sic] presence on the sanction list… UBS has announced that they will immediately close our accounts,” the letter published online reads.
“It was only a question of time until we face this serious problem.”
The letter adds: “We have to look for a new bank connection. In the process of this change we anticipate some problems.”
Mr Ilyumzhinov is yet to comment on FIDE’s letter. He is still listed as the organisation’s president on its website.
In March 2017, Mr Ilyumzhinov was quoted by Russia’s Tass news agency as saying that FIDE, the governing body of international chess competitions, was trying to “oust” him after a statement on it’s website said he had resigned.
“I think there is an American hand in this, and I think it’s called a set-up,” he said.
Mr Ilyumzhinov, a former businessman and politician, has long been viewed as an eccentric character.