The Donald Trump and Kamala Harris campaigns are sparring over whether to mute one of the microphones when it is the other person's turn to speak during the pair's scheduled debate next month.
The Harris campaign said in a statement to the BBC's US partner CBS News that it wanted both candidates’ microphones to be live throughout the full broadcast.
The Trump campaign reportedly wants the ABC debate, scheduled for 10 September, to be governed by the same rules agreed when Joe Biden was the Democratic candidate. That would mean the microphones being muted.
The apparent impasse comes as the former president questioned the impartiality of the network and signalled he might even skip the debate.
The deadlock in negotiations between the two campaigns was first reported by Politico.
Before President Joe Biden stepped down as the Democratic party nominee, his campaign agreed with Trump's campaign to participate in two debates - one previously held in June on CNN and one to air on ABC News this September.
The Biden campaign negotiated the rules for the debate and agreed that the microphone would be muted when a candidate wasn't speaking.
The Trump campaign agreed to the rule, which was enforced during the June CNN debate.
But now, with just 15 days until the ABC News debate is scheduled to air, the Harris campaign wants the microphones to be "hot" - meaning it will never be turned off for the duration of the debate.
"We have told ABC and other networks seeking to host a possible October debate that we believe both candidates’ mics should be live throughout the full broadcast," Harris campaign senior communications adviser Brian Fallon said in a statement.
"The vice president is ready to deal with Trump’s constant lies and interruptions in real time. Trump should stop hiding behind the mute button," he added.
This allows the two candidates to interrupt and speak over each other on the debate stage.
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Trump's campaign accused Ms Harris of finding a way to get out of the debate with Trump.
“Enough with the games. We accepted the ABC debate under the exact same terms as the CNN debate," senior Trump adviser Jason Miller told Politico. "The Harris camp, after having already agreed to the CNN rules, asked for a seated debate, with notes, and opening statements. We said no changes to the agreed upon rules.”
A Harris campaign official who was asked about the Trump campaign's claims said they are "100% false", according to CBS News.
On Trump's Truth Social platform on Sunday, he questioned whether the ABC News journalists moderating the debate will give the questions to the Harris campaign ahead of time.
"Why would I do the debate against Kamala Harris on that network?" he wrote.
This is not the first time the former president has suggested he would back out of the debate. Earlier this month, Trump said he would only debate Ms Harris if the debate was hosted by Fox News. He reversed course several days later.
As the election nears, the Harris campaign has raised $540 million since Biden stepped down, the Associated Press reports. Harris saw record-breaking fundraising numbers in the aftermath of Mr Biden dropping out of the race.
The Trump campaign, on the other hand, raised $138.7 million in July and has $327 million cash on hand.
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