Boris Johnson and Jeremy Corbyn have clashed over their rival visions for Brexit in the final head-to-head TV debate of the General Election campaign.

With less than a week to polling day, the Labour leader warned of "chaos" and "huge job losses" if a Tory government was unable to get a free trade deal with the EU by the end of the year.

Mr Corbyn highlighted leaked Treasury documents released earlier in the day which he said showed Mr Johnson's withdrawal agreement meant there would be customs checks and restrictions on trade between Britain and Northern Ireland.

Appearing before a live studio audience in Maidstone in a debate hosted by the BBC, the Prime Minister retorted that the claims were "not true".

He added: "I do find it slightly curious to say the least to be lectured about the union between Great Britain and Northern Ireland by a man who all his political life has campaigned to break up that union and actually supported for four decades the IRA their in their campaign violently to destroy it."

Mr Corbyn in turn challenged Mr Johnson to show a "degree of honesty" about the arrangements he had made for Northern Ireland.

He said: "He spoke at the DUP conference and said there would be no restrictions whatsoever. We now know there are restrictions. He could and should have said that at the time."

Mr Johnson questioned how Labour could negotiate a new Brexit deal as it has pledged to do when Mr Corbyn was "neutral" and other frontbenchers were pro-Remain.

"Who is going to negotiate it because as far as I can see everybody on the Labour frontbench is campaigning to Remain apart from Mr Corbyn who is neutral on the matter?" he said.

"How can you get a deal, a new deal from Brussels for Brexit, if you don't actually believe in it? That's the mystery that I fail to understand."

Mr Johnson also brushed off an intervention by former prime minister Sir John Major who suggested he would back former Tory MPs now standing as independents after having the whip withdrawn.

"Unlike Mr Major, I lead a party that is now totally united," he said