The Manhattan district attorney's office has recently threatened to file new criminal charges against former Trump Organization chief financial officer Allen Weisselberg, sources familiar with the matter told ABC News.
Weisselberg, 75, is currently serving jail time at New York's Rikers Island after he pleaded guilty to tax fraud in August.
The new charges, the sources said, would involve insurance fraud, a detail first reported by The New York Times.
Prosecutors in Manhattan are using the threat of additional charges to pressure Weisselberg into cooperating with their ongoing criminal investigation into former President Donald Trump and his business, the sources said.
A spokesperson for District Attorney Alvin Bragg declined to comment to ABC News. An attorney for Weisselberg also declined to comment.
Weisselberg testified against the Trump Organization at its criminal trial last year as part of a plea agreement, but he did not implicate the former president in the company's tax fraud.
Insurance fraud was mentioned in New York Attorney General Letitia James' $250 million civil lawsuit that the AG brought in September against Trump, his eldest children, and his business. The lawsuit, which also names Weisselberg and other executives, alleges that the former CFO lied to an insurance company about an appraisal of Trump's real estate portfolio.
Trump has denied wrongdoing and has called James' investigation a politically motivated "witch hunt."
This week, prosecutors began presenting evidence to a grand jury investigating whether Trump played a role in the hush money payment to Stormy Daniels ahead of the 2016 presidential election. Among the initial witnesses, ABC News has previously reported, were former National Enquirer publisher David Pecker and Trump Organization controller Jeff McConney.
Trump has denied knowing about the payment, which was arranged through his then-personal attorney, Michael Cohen.