The businessman is seeking to recover up to $500 million from UBS that he lost after the bank called in a margin loan, «Bloomberg» reported on Friday. According to Guo, the Swiss bank's' forced the sale of the stock amid a market rout and a 45 percent plunge in Haitong's Hong Kong-traded shares in 2015 wiped out his investment.

UBS said in a statement that «strongly disagrees with the claim and will vigorously defend itself.» The tycoon has been in self-imposed exile in New York since 2017, where he conducts a political agenda to bring attention to alleged corruption in the Chinese political system.

Chinese Sought Extradition

In 2017, U.S. President Donald Trump refused Chinese requests to deport Guo, a member of Trump's Mar-a-Lago resort. Guo is also known for his close ties to former White House chief strategist Steve Bannon, with whom he declared a «New Federal State of China» that «would overthrow the Chinese government.»

In August, Bannon was arrested by U.S. authorities while on Guo's $35 million luxury yacht docked in Connecticut and charged with stealing millions of dollars from the «We Build the Wall» non-profit organization.