Boris Johnson and Jeremy Corbyn will go head-to-head for the second time later, in a live BBC election debate.
The hour-long BBC One programme, hosted by the Today presenter and ex-political editor Nick Robinson, starts at 20:30.
It comes as the BBC’s Andrew Neil challenged the prime minister to submit to a half-hour TV grilling.
The other main party leaders have been interviewed by Neil – but the Tory leader has yet to agree and has also pulled out of an ITV interview.
Labour leader Jeremy Corbyn was interviewed by ITV’s Julie Etchingham on Thursday night, but the prime minister has declined an invitation to take part in the channel’s series of leader interviews.
In a monologue at the end of Thursday’s programme – where he had interviewed Brexit Party leader Nigel Farage – Mr Neil issued a challenge to Mr Johnson.
“It is not too late. We have an interview prepared. Oven-ready, as Mr Johnson likes to say,” he said.
“The theme running through our questions is trust – and why at so many times in his career, in politics and journalism, critics and sometimes even those close to him have deemed him to be untrustworthy.
“It is, of course, relevant to what he is promising us all now.”
The Conservative Party has yet to respond to Mr Neil’s statement, although the PM has in the past rejected opposition claims he is avoiding scrutiny, pointing out that he has taken part in debates and interviews during the campaign with the BBC and other broadcasters.
Labour has accused the BBC of bias, in a letter to Director General Tony Hall.
Campaign co-ordinator Andrew Gwynne accused the corporation of being effectively “complicit in giving the Conservative Party an unfair electoral advantage”.
He said Labour had agreed to Mr Corbyn’s interview with Mr Neil based on the “clear understanding” that the Tory leader had agreed the same terms.
The BBC is expected to respond in writing to the Labour complaint, but a spokesperson said: “The BBC will continue to make its own independent editorial decisions, and is committed to reporting the election campaign fairly, impartially and without fear or favour.”
Liberal Democrat leader Jo Swinson said: “Boris Johnson must stop ducking scrutiny. His cowardly behaviour shows why he simply isn’t fit to be prime minister.”
She said it was “bad enough” that her party had been “excluded” from the BBC’s head-to-head debate between Mr Johnson and Mr Corbyn, and “even worse that right now Boris Johnson won’t be held properly to account for his lies and extreme Brexit plans”.
In the hour-long Prime Ministerial Debate on Friday evening, Mr Johnson and Mr Corbyn will face questions from the audience in Maidstone, Kent and from those who have submitted them via the BBC News website.
It will be the last scheduled meeting between the two party leaders before next Thursday’s general election.
Mr Johnson and Mr Corbyn faced each other last month in the ITV election debate, when they clashed on Brexit, the NHS, trust and leadership, the future of Scotland – and the Royal Family.
Following that debate, BBC political editor Laura Kuenssberg said it was not clear if either man had won or lost the debate but it was striking how the audience had been ready to laugh at their statements.
A snap YouGov poll suggested the public were evenly split on who had won the debate “with most Labour voters thinking Jeremy Corbyn won, most Conservative voters thinking Boris Johnson won”.
How can I follow the programme live?
It will be televised live in the UK on BBC One and on BBC iPlayer and streamed live on the BBC News website, which can be viewed from outside the UK, where you can also follow the latest reaction and analysis on our live page.
It will also be broadcast live on BBC Radio 5 Live and on the BBC Sounds app.