Founder of the Baring Vostok private equity group Michael Calvey, who was detained on suspicion of fraud, stands inside a defendants' cage as he attends a court hearing in Moscow, Russia February 15, 2019. REUTERS/Tatyana Makeyeva

MOSCOW (Reuters) - German Gref, the chief executive of Russia’s biggest state lender Sberbank, said on Friday he hoped the criminal case against Baring Vostok’s founder Michael Calvey would turn out to be a misunderstanding.

U.S. national Calvey has been detained on suspicion of fraud and a court is set to rule on whether to hold him in custody later on Friday. Gref said in a statement that he knew Calvey to be an honest and decent person.