Robert C. Trosten, the former chief financial officer of foreign exchange company Refco, has been charged with defrauding investors in a scheme which resulted in a loss of more than $1bn (£533m).

In a US District Court in Manhattan ,Trosten was also charged with assisting Phillip R. Bennett, formerly Refco's chief executive officer, in allegedly hiding hundreds of millions of dollars of debt owed to Refco by a company controlled by Bennett.

Trosten denies any wrongdoing.

‘Robert Trosten denies that he intentionally engaged in any fraud and looks forward to establishing his innocence at trial,’ his lawyer, Robert Morvillo, was reported as saying.