United States Vice President Kamala Harris and former US President Donald Trump have settled on the ground rules for their first debate following a dispute over whether their microphones should be kept on throughout the event.

ABC News on Wednesday confirmed the format for the September 10 debate after the disagreement over microphones had threatened to derail the first – and, so far, only confirmed – face-off between the Democratic and Republican nominees.

ABC News said Trump would give the last closing statement and stand on the left of the screen after winning a virtual coin flip.

The 90-minute debate will be held at the National Constitution Center in Philadelphia and feature no audience.

The announcement came after the Harris campaign agreed that the microphones would be muted when it is the other candidate’s turn to speak.

Her campaign had pressed to keep the microphones on at all times, arguing she should have the opportunity to “deal with Trump’s constant lies and interruptions in real-time.”

In a letter to ABC News after agreeing to the rules, the Harris campaign said it would be “fundamentally disadvantaged by this format”, but it did not wish to “jeopardise the debate”.

Trump said last week he would “probably” keep the microphones on, but “the agreement was that it would be the same as it was last time”.

Before dropping his bid for re-election, US President Joe Biden had insisted on muted microphones to stop Trump from interrupting him while speaking.

Harris and Trump both agreed to a debate on September 10, but the event had been in question in recent weeks after the sides clashed over the microphone rules and the Republican candidate suggested that he might back out.