Shvidler was sanctioned by the U.K. in March for his ties to Abramovich, his long-time best friend and business partner. The duo made their fortunes in tandem during the oil privatization boom in 1990s Russia.

He was born in the Soviet Union, but today is a citizen of both the U.K. and the U.S., having previously lived in New York while working for the audit and consulting firm Deloitte.

Shvidler declined to comment on his assets. A spokesman said he does not hold Russian citizenship, and has not been to the country since 2007, adding: “There are no ties to the Kremlin.”