As Sunak and Truss clashed over the cost of living, NHS funding and the economy in the TalkTV/Sun debate on Tuesday night, a loud crash interrupted the two Tory rivals.
The foreign secretary, who looked visibly startled, said “oh, my god” before leaving the podium as the broadcast cut out.
A TalkTV statement said: “Kate McCann fainted on air tonight and although she is fine, the medical advice was that we shouldn't continue with the debate. We apologise to our viewers and listeners."
McCann became the political editor at TalkTV this year after working as a political correspondent at Sky News.
A video of Truss' reaction to the incident was posted on Twitter.
— Harry Rutter (@harryjohnrutter) July 26, 2022
The programme immediately went off-air, with a message appearing on the screen, saying: “We are sorry for the disruption to this programme.
“We are working hard to fix the issue and will return to normal programming soon.”
Following the incident, both leadership hopefuls tweeted messages of support for McCann.
"Good news that you're already recovering Kate McCann," said Sunak on Twitter. "It was a great debate and I look forward to getting grilled by you again shortly!"
Truss said: "Relieved to hear Kate McCann is fine. Really sorry that such a good debate had to end. "Look forward to catching up with Kate and the rest of The Sun and Talk TV team again soon."
Prior to the debate being halted, McCann had quizzed the pair on tax, NHS funding, and Russia.
Sunak claimed he had been "brave" to introduce the national insurance hikes earlier this year which raised £12bn in revenue to fund health and social care.
"It wasn’t an easy thing for me to do," said the former chancellor.
"I got a lot of criticism for it, but I believe it was the right thing to do as I don’t think we can have an NHS which is ultimately the country’s number one public service priority that is underfunded and not able to deliver the care it needs."
Truss said, while she is "committed" to the extra £12bn for the NHS, it should come from "general taxation" instead of tax hikes.
The foreign secretary also said tax increases on families were "morally wrong" during a cost-of-living crisis - which was rebuffed by Sunak, who said it was “morally wrong” to put more debt on future generations.
Their remarks come as the pair continue to battle for the support of the Tory membership base in the race for the keys to Number 10.
Tory members will vote on their preferred candidate over the summer, and the new prime minister is set to be announced on 5 September.
Truss is currently the overwhelming favourite with a poll published by YouGov on Thursday showing Truss leads at 62% among members versus Sunak's 38%.
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