Boris Johnson and Jeremy Corbyn were almost inseparable in the eyes of viewers after a series of heated exchanges during the first televised debate of the General Election.

Mr Johnson edged a snap YouGov poll 51-49 although Labour figures were pleased with the showing of their leader in the prime-time ITV slot.

The pair clashed over their rival plans for Brexit, with Mr Corbyn describing the Prime Minister’s pledge to “get Brexit done” by the end of January as “nonsense”, while Mr Johnson suggested his rival was “not fit to lead our country”.

Mr Corbyn also accused the Government of entering into secret talks with the US to open the NHS to American pharmaceutical companies in a future trade deal.

But Mr Johnson hit back, denouncing the claims as “an absolute invention”, insisting there were “no circumstances whatsoever” in which a Conservative government would put the NHS “on the table” in trade talks.

He said the Labour leader was trying to disguise the “void” at the heart of his Brexit policy, which meant he was unable to say which way he would vote in Labour’s planned second referendum.

He accused Mr Corbyn of being prepared to strike a deal with the SNP’s Nicola Sturgeon to get the votes he needs to enter No 10 at the price of a second referendum on Scottish independence, something the Labour leader rejected.

YouGov’s poll, which surveyed 1,646 viewers, also found Mr Johnson appeared more prime ministerial, although Mr Corbyn was considered more trustworthy.

The Conservatives also courted controversy for changing their Twitter handle to “factcheckUK” for the ITV debate, prompting fact-checking organisation Full Fact to label it “inappropriate and misleading”.

And Mr Johnson dropped a hint about the Tory manifesto when asked if social care would be included, saying: “Yes there will and we think that nobody should pay for the cost of their social care by selling their home and everybody should have dignity and security in their old age.”

The Liberal Democrats are expected to launch a fully-fledged manifesto on Wednesday, which will aim to build on a series of previously announced pledges.

These include an attempt to raise £35 billion for health and social care via a penny increase on income tax, an extra £10 billion a year on schools, a bid to recruit 20,000 more teachers, and scrapping business rates to help the high street.

The debate came as:

– The Conservatives pledged an extra £15 million for the criminal justice system to speed up prosecutions for rape.

– Labour said it would aim to “wage war” on poverty if elected via policies designed to eradicate low par and food bank use.

– The Institute for Fiscal Studies said the revenue raised by Labour’s proposed income tax changes was “highly uncertain”.

– The Archbishops of Canterbury and York issued an appeal to voters and politicians to “honour the gift of truth” during the election campaign.

Further leaders’ events are planned for the election, with the BBC hosting a Question Time special on Friday.