A former colleague of Lord Conrad Black has agreed to pay $28.7m (£14.7m) to the US authorities to settle fraud charges against him.
Conrad Black faces a lengthy prison sentence if convicted
David Radler, once chief operating officer of media firm Hollinger International under Lord Black, had admitted financial impropriety.
Mr Radler agreed to co-operate with the authorities in 2005 in return for a 29-month jail sentence.
Mr Radler is expected to testify against Lord Black in his fraud trial.
Opening statements in the trial, in which Lord Black and three others are accused of defrauding Hollinger International shareholders of $85m, begin on Monday.
Lord Black and his co-defendants have denied all the charges.
The Securities and Exchange Commission confirmed the settlement with Mr Radler, which bars him from ever becoming a director of a public company again.
"Radler and others misappropriated millions of dollars from Hollinger International and made numerous misstatements to shareholders as part of their scheme," said Linda Chatman Thompson, director of the SEC's enforcement division.
"The tough sanctions in this settlement reflect our resolve to act forcefully against corporate officers who perpetrate fraud against those whom they were supposed to serve, the shareholders of the company."
Mr Radler had pleaded guilty to a single count of fraud and agreed to co-operate with the authorities in return for a truncated jail sentence.
Prosecutors have accused Lord Black and his co-defendants of illegally enriching themselves and others by using a series of "non-compete clauses" to divert money from the sale of newspapers owned by Hollinger International.
Lord Black and Mr Radler treated Hollinger International as "their personal piggybank", the SEC said in 2004.
Following jury selection on Thursday, Lord Black said that he had every confidence that he would be cleared.
The trial is expected to last up to four months.