Donald Trump tried to illegally influence the 2016 US presidential election by paying hush money to porn star Stormy Daniels, prosecutors alleged on Monday.

The former US president faced court in Manhattan on 34 felony counts of falsifying business records over payments he made to his former lawyer, Michael Cohen, that prosecutors say were reimbursements for money paid to Daniels in order to bury her claims of a sexual encounter.

"This was a planned, long-running conspiracy to influence the 2016 election, to help Donald Trump get elected through illegal expenditures to silence people who had something bad to say about his behavior," prosecutor Matthew Colangelo told the court.

"It was election fraud, pure and simple."

Trump's lawyers rejected the allegations during the hearing.

"I have a spoiler alert: there's nothing wrong with trying to influence an election," attorney Todd Blanche said. "It's called democracy."

Trump off the campaign trail

The trial could last up to two months and requires Trump — who is the favorite in the Republican presidential primaries — to spend his days in a courtroom rather than on the campaign trail.

"I'm the leading candidate ... and this is what they're trying to take me off the trail for. Checks being paid to a lawyer," Trump said after the hearing on Monday.

A guilty verdict would not preclude Trump from becoming president again, but he would not be able to pardon himself because it is a state case rather than a federal case.

The former US president also faces separate indictments on charges of conspiring to overturn the results of the 2020 election won by Biden and for hoarding secret documents at his Mar-a-Lago mansion in Florida, both of which he denies.

While those cases have been repeatedly delayed due to challenges by his legal team, the New York hush money case has so far run on schedule.

zc/fb (AP, AFP)