A judge in New York has warned Donald Trump that he could be placed in jail if he continues to violate a gag order during his trial over alleged hush money payments.

Justice Juan Merchan handed a written order to the former president telling him the court will ‘consider a jail sanction’ if he does not keep to the terms of the order.

The judge said: ‘It is important that you understand that the last thing I want to do is put you in jail.’

However, he added that the violations were ‘a direct attack on the rule of law’ and that his ‘job is to protect the dignity of the judicial system’.

It is the most serious rebuke of Trump so far in his criminal trial, the first to ever be held for an ex-US president.

Trump is accused of working with a tabloid publisher to prevent lurid stories about his sex life becoming public during his 2016 presidential run.

Since the trial began on April 15, Mr Trump has been subject to a gag order telling him not to make public statements about people involved in the case.

Last week, he was fined $9,000 by the court for violating the terms of the order.

But he made further comments on a right-wing TV network suggesting the jury is ‘95% Democratic’ and saying the judge is ‘rushing the trial like crazy’.

He had been fined a further $1,000 as a result, and given the letter raising the possibility of incarceration.

In his ruling, Judge Merchan writes that Mr Trump ‘violated the Order by making public statements about the jury and how it was selected.

‘In doing so, Defendant not only called into question the integrity, and therefore the legitimacy of these proceedings, but again raised the specter of fear for the safety of the jurors and of their loved ones.’