Washington DC: US President Donald Trump and Democratic challenger Joe Biden will have their microphones muted for parts of their final debate on Thursday to allow each candidate a block of uninterrupted time to speak and avoid the rancour of the two candidates’ first encounter.

The Commission on Presidential Debates, the sponsor of the televised debate in Nashville, said changes were necessary after the bad-tempered first debate.

When one of the two candidates is given a chance to provide a two-minute answer to each of the six debate topics, his opponent’s microphone will be muted, the Commission on Presidential Debates said in a statement.

“It is the hope of the Commission that the candidates will be respectful of each other’s time, which will advance civil discourse for the benefit of the viewing public,” the statement said.

The final debate scheduled between Trump and Biden is set for Thursday at 9 pm ET in Nashville. It will be moderated by NBC News’ Kristen Welker. It will run 90 minutes in length, with each of the six topics allotted 15 minutes.

Trump’s campaign objected to the change but said he would still take part.

Trump campaign manager Bill Stepien in a statement accused the commission of bias but said the president “is committed to debating Joe Biden regardless of last minute rule changes.”

Stepien’s statement also signaled that Trump would bring up allegations against Biden’s son, Hunter Biden, during the debate.

The commission is a non-partisan body.

Trump later told reporters he would take part.

“I will participate but it’s very unfair that they changed the topics and it’s very unfair again that we have an anchor who’s totally biased,” he claimed.