Special counsel Robert Mueller filed new charges Thursday against former Trump campaign chairman Paul Manafort and his longtime associate, Rick Gates, for money laundering and bank fraud.

The new criminal charges are reportedly not connected to Manafort and Gates’ work with President Trump’s campaign. According to the unsealed court documents, Mueller’s investigation learned that the men had passed over $75 million through offshore accounts. Manafort is accused of laundering over $30 million to pay for real estate and luxury goods, and Gates is accused of transferring over $3 million from offshore accounts.

Friday, the New York Times reported that Gates is expected to plead guilty “as soon as Friday afternoon, according to two people familiar with his plea agreement, a move that signals he is cooperating with the investigation into Russia’s interference in the 2016 election.”

The plea deal could be a significant development in the investigation — a sign that Mr. Gates plans to offer incriminating information against his longtime associate and the former campaign chairman, Paul Manafort, or other members of the Trump campaign in exchange for a lighter punishment.

The deal comes as the special counsel, Robert S. Mueller III, has been raising pressure on Mr. Gates and Mr. Manafort with dozens of new charges of money laundering and bank fraud that were unsealed on Thursday. Mr. Mueller first indicted both men in October, and both pleaded not guilty.

Mr. Gates’s primary concern has been protecting his family, both emotionally and financially, from the prospect of a drawn-out trial, according to a person familiar with his defense strategy who was not authorized to publicly discuss the case and spoke on the condition of anonymity.