Jeremy Corbyn is to take part in a live TV general election debate which is being boycotted by Theresa May.
The Labour leader will join the leaders of the Liberal Democrats, Ukip, the Green Party and Plaid Cymru, and the SNP's leader at Westminster, in the BBC Election Debate.
But Conservatives will be represented by Home Secretary Amber Rudd, after the Prime Minister made clear that she is not willing to take part in head-to-head debates with any other party leaders during the campaign for the June 8 election.
Speaking to a rally of supporters in Reading, Mr Corbyn issued a challenge to Mrs May to join him at the debate in Cambridge.
The Labour leader said: "It's very odd that we have an election campaign where we go out and talk to people all the time and the Prime Minister seems to have difficulties in meeting anyone or having a debate.
"There is a debate in Cambridge tonight.
"I don't know what she is doing this evening, but it's not far from London.
"I invite her to go to Cambridge and debate her policies, debate their record, debate their plans, debate their proposals and let the public make up their mind."
Aides confirmed Mr Corbyn would be taking part in the seven-way TV broadcast.
Before he announced he would take part, Mr Corbyn directly challenged Mrs May to debate him on television, which she has refused to do.
The Labour leader told a Westminster press conference on Wednesday morning: "There's something very odd about going down to Sky the other night, me being brought in front of the audience, very happy to do so and answer questions from the audience, sat in front of Jeremy Paxman, an utter pleasure it was too, to be having a chat with Jeremy Paxman for a while, there's no finer way to spend a Monday evening.
"And then the Prime Minister is hiding away in a room upstairs to come down and do exactly the same, how ridiculous is that?
"Come on Prime Minister, come and have a chat, come and have a debate and I can be ever so polite, but there are a number of questions I want to put to you."
He added: "I know she's not too busy because she's not planning a debate today but why not change your mind? Come and have a debate."
Mr Corbyn has cancelled planned appearances at stump events in Swindon and Stroud, and a rally in Bristol.
The events will go ahead with shadow education secretary Angela Rayner and shadow health secretary Jon Ashworth filling in, a Labour source said.
Also appearing in the BBC debate will be Lib Dem leader Tim Farron, Ukip's Paul Nuttall, Green co-leader Caroline Lucas, Plaid Cymru's Leanne Wood and the SNP's depute leader Angus Robertson, who leads the party's MPs at Westminster.
Ms Lucas welcomed Mr Corbyn's decision, saying: "Great news, Jeremy Corbyn. Now will Theresa May crawl out from where's she's hiding to debate?"
The Green co-leader said: "Failing to show up to tonight's debate would show extreme cowardice from a Prime Minister resolutely avoiding proper scrutiny.
"Our democracy deserves proper debate between party leaders, not just setpiece speeches and one-to-one interviews and Q&As.
"Theresa May said she called this election because of the actions of other parties, yet she's unwilling to debate with us on the big issues of the day.
"It is a sign of extreme weakness for a Prime Minister to avoid these debates."
Mr Robertson said: "Theresa May called this election in the hope of crushing parliamentary opposition but instead the campaign has exposed her weak and wobbly leadership, as well as Tory plans to attack the incomes of older people and their increasingly reckless approach to Brexit.
"Indeed, tonight Amber Rudd must explain why she believes that the people of Scotland should entrust their future to people like Boris Johnson, when she herself said during last year's referendum campaign that he was 'misleading the public' on the EU."
Supporters who were planning to attend the rally in Bristol expressed their disappointment over Mr Corbyn's cancelled appearance on the event's Facebook page, but interpreted his decision to attend the debate as a shrewd move.
One user, Helen Robinson said: "Yeah, it's a good move for JC. Was really buzzing about this though."
Another, Mandy Robinson, replied to say she had cancelled plans to attend.
"Yeah I cancelled all sorts of other stuff," she wrote.
Another, Gav Forsyth, wrote: "Aww jez. I made a sign and everything."
The 90-minute debate, on BBC1 at 7.30pm on Wednesday evening, follows a series of election broadcasts including a Sky News/Channel 4 programme on Monday evening in which Mrs May and Mr Corbyn separately took questions from a studio audience and were interviewed by veteran interrogator Jeremy Paxman.
TV leaders' debates first became a feature of UK general elections in 2010 when David Cameron, Gordon Brown and Nick Clegg took part in three live clashes.
The 2015 campaign featured a duel between Mr Cameron and Labour leader Ed Miliband, as well as a seven-way debate also including the Liberal Democrats, Ukip, SNP, Plaid Cymru and the Greens and a five-way opposition debate in the absence of the Tory and Lib Dem leaders.
Mr Corbyn told supporters: "I have to go now because I am going to Cambridge to get ready for the debate tonight.
"We'll put our views out there and let the people decide: for the many, not the few."
Amber Rudd will still appear for the Conservatives at the debate.
A Conservative Party spokesman said: "There are no changes to the Prime Minister's plans. She is out campaigning today, engaging with voters about the issues that matter, not swapping soundbites with six other politicians.
"There is a clear choice in this election: either the Brexit negotiations are led by Theresa May 11 days after polling day, or they will be put at risk by Jeremy Corbyn and his coalition of chaos."
A Conservative source said: "The public want to see a leader who can stare down the EU-27 at the negotiation table, not someone who will need their iPad to remember their dodgy facts in a debate."