Special counsel Robert Mueller has filed additional charges against President Donald Trump’s former campaign chairman Paul Manafort and a business associate.

The filing adds allegations of tax evasion and increases the amount of money Manafort is accused of laundering through offshore accounts to 30 million dollars (£21.5 million).

The additional charges involve much of the same conduct Manafort and his longtime associate, Rick Gates, were charged with last year in an indictment in Washington.

The two men were initially charged in a 12-count indictment last October that accused them of a multimillion-dollar money-laundering conspiracy tied to their foreign lobbying work.

Trump Guns
Paul Manafort is Donald Trump’s former campaign chairman (Evan Vucci/AP)

The new indictment comes a week after Mr Mueller filed charges against 13 Russians, accusing them of a vast conspiracy to undermine the US presidential election.

The charges against Manafort and Gates do not relate to any allegations of misconduct related to Trump’s campaign.

Both men pleaded not guilty after they were initially charged in October.

The new indictment accuses Manafort and Gates of doctoring documents to inflate the income of their businesses and then using those fraudulent documents to obtain loans.

It also accuses Manafort of evading taxes from 2010 through 2014 and in some of the years concealing his foreign bank accounts.

In a document that accompanied the new indictment, prosecutors said they had filed the charges in Virginia, rather than Washington where the other case is pending, because the alleged conduct occurred there and one of the defendants objected to them being brought in Washington.

AP