Theresa May has resisted pressure to take part in live TV debates with rival leaders, after Jeremy Corbyn dramatically announced he would join a set-piece clash and threw down the gauntlet for her to join him.
With opinion polls showing Labour closing the gap on the Conservatives, Mr Corbyn scrapped planned campaign visits in the West Country to travel to Cambridge for the BBC Election Debate, expected to attract an audience of millions on Wednesday evening.
Mrs May faced accusations of "extreme cowardice" as the Tories confirmed they would be represented by Home Secretary Amber Rudd, while other parties send their leaders - or in the case of the Scottish National Party, its leader in Westminster.
But the Prime Minister insisted she wanted to focus her campaign on meeting voters and answering their questions, rather than "squabbling" with other politicians.
Mrs May brushed off a seat projection by pollster YouGov for The Times, which suggested the UK could be heading for a hung parliament, with Labour making gains while Tories lose seats.
Answering questions during a factory visit in Bath, she insisted that "there's only one poll that matters and that's the poll that takes place on June 8".
"I think debates where the politicians are squabbling amongst themselves doesn't do anything for the process of electioneering," she said.
"I think it's actually about getting out and about, meeting voters and hearing directly from voters."
Announcing his decision to attend during a rally in Reading, Mr Corbyn said he had been meeting people across the country during the campaign, while Mrs May "seems to have difficulties in meeting anyone or having a debate".
He said: "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."
Green co-leader Caroline Lucas said Mrs May's decision showed "extreme cowardice", while Liberal Democrat leader Tim Farron said she was "clearly terrified of having to defend the cruel and heartless policies in the Conservative manifesto".
Lib Dems accused Mrs May of "keeping voters in the dark" about her plans if she holds on to power, releasing a list of 20 policies in the Tory manifesto which are subject to review or consultation after the election - ranging from social care funding to winter fuel payments and energy bill caps.
Mr Corbyn went on the attack over public services, warning that under Tory plans, 5.5 million people will find themselves on NHS waiting lists in England by 2022, 1.5 million older and vulnerable people will not have their social care needs met and 650,000 school children will be in classes of 30 or more.
The Labour leader turned Mrs May's election slogan against her, claiming that after seven years of Conservative-led administrations, the state of health, social care and education was "anything but strong and stable".
But Conservatives dismissed Mr Corbyn's figures as "dodgy", pointing to official statistics showing falling NHS waiting times and hospital deficits, as well as their own manifesto promise to increase real-terms spending on schools.
"Jeremy Corbyn's shaky grip on the facts clearly hasn't improved since his car crash interview about childcare costs yesterday," said a Conservative spokesman.
"This shambolic failure to grasp detail shows exactly why Corbyn isn't up to the job of negotiating Brexit - in contrast to Theresa May's clear plan to stand up for Britain and get the best deal."
Labour played down reports that Mr Corbyn could open the door to unskilled foreign workers as part of his immigration shake-up, insisting the document leaked to the Daily Telegraph and Daily Mail was a discussion paper and "not a statement of Labour policy".
Mrs May sought to force the focus of the election campaign back on to her favoured topics of leadership and Brexit, repeating her warning that Mr Corbyn is not prepared for negotiations which will begin 11 days after the election.
Voters were faced with a "very clear choice" on June 8, she said, adding: "That choice is about who is going to be prime minister, who is going to lead the UK in those Brexit negotiations, who has the plan to do that, the determination to get the best deal, who has the strong and stable leadership to do that."
The Press Association's poll of polls, a seven-day rolling average of all published polls, puts the Conservatives on 44% and Labour on 35%.
The Financial Times announced its support for the Conservatives, but said "neither of the main party leaders is particularly impressive" and the lack of clarity from both sides on Brexit was "deeply unsatisfactory".
It noted that "far from being strong and stable, Mrs May has looked curiously brittle" and criticised her plans to meddle in the markets and curb immigration.
But she was a "safer bet" than Mr Corbyn, who "is a pacifist relic of the 1970s, in hock to the trade unions, with no grip on economic issues", the FT said in a leader column on its website.
The newspaper backed a continuation of the powersharing between the Tories and Liberal Democrats in 2015.