The prime minister is the only major party leader yet to commit to a grilling from the BBC’s vastly-experienced political interviewer.
Labour agreed to the interview after being told Johnson would do it next week - crucially after postal ballots for the December 12 election are sent out this week.
And the PM may be hoping a delay will help him squeeze out some extra votes, with experts expecting around a quarter (25%) to be cast by post, and the biggest return over the first weekend after they are received.
A Tory spokesperson would say only that “negotiations are still ongoing” with the BBC.
The broadcaster also said it has not been able to fix a date with the Tories.
Scottish first minister Nicola Sturgeon and Jeremy Corbyn were interviewed by Neil on Monday and Tuesday respectively this week, with the Labour leader suffering a rough ride over his party’s record on anti-Semitism and its tax and spending plans.
It is understood that the BBC had planned a third special interview with Neil on Wednesday night, which was mysteriously cancelled and replaced with his regular show featuring multiple guests.
Liberal Democrat leader Jo Swinson and the Brexit Party’s Nigel Farage will face Neil next week.
Labour party chair Ian Lavery accused Johnson of “running scared” from Neil.
“Boris Johnson backed out of a head-to-head debate with Jeremy Corbyn on Sunday, he is refusing to take part in the party leaders’ climate crisis debate tomorrow and now this,” he said.
“He’s running scared because every time he is confronted with the impact of nine years of austerity, the cost of living crisis and over his plans to sell out our NHS, the more he is exposed.”
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