US prosecutors have accused Donald Trump’s former campaign manager, Paul Manafort, of trying to tamper with potential witnesses ahead of his trial.
Robert Mueller, who is investigating alleged Russian election interference, said Mr Manafort had contacted people related to his money laundering and tax fraud case in breach of his bail terms.
Mr Manafort, 69, denies all charges.
They are not connected with allegations of collusion between Russia and the Trump campaign during the US election.
Mr Trump denies any collusion and has consistently spoken of a witch hunt.
Mr Manafort’s first trial, on charges of money laundering and illegal lobbying, is due to begin in September.