Jeremy Hunt and Boris Johnson have clashed over Brexit in the only head-to-head debate of the Tory leadership campaign - with Johnson refusing to rule out suspending Parliament to force through no-deal.

The two contenders bidding to replace Theresa May met in Manchester to face off before a live studio audience, chaired by ITN's Julie Etchingham and shown on STV.

Johnson urged Conservative party members to vote for him to reject the "can-kicking approach" to Brexit, vowing to deliver it on October 31 as the only way "to get this country off the hamster wheel of doom".

Hunt said the former London mayor's "do or die" approach to the EU exit deadline risked a general election.

The foreign secretary vowed to "bring together our amazing United Kingdom" - but beyond that, the hour-long programme did not feature a single mention of Scotland or the union.

Johnson used his opening statement to promise he would give the UK its "mojo" back, while Hunt touted his credentials as a "tough negotiator" to bring about a Brexit deal.

He repeatedly challenged Johnson to say whether he would resign if he failed to deliver Brexit on October 31.

Johnson answered: "My opponent is clearly not committed to coming out of the EU on October 31...

"I think it's very, very important not to envisage any circumstances in which we would fail to come out of the EU on October 31.

"I don't want to hold out to the EU the prospect that they encourage my resignation by refusing to agree a deal."

In a swipe at his rival, he claimed the EU will not take the UK seriously if there is a "papier-mache" Brexit deadline.

Johnson added: "Nor will business understand that they must prepare for no-deal."

"It's not do or die, is it? It's Boris in Number 10 that matters," replied Hunt.

The foreign secretary, whose birthday is on November 1, earlier said "nothing would be a better birthday present than knowing we have left on the October 31".

He said Johnson's rigid commitment to the Halloween deadline would make a general election a significant risk, but the ex-London mayor responded it was "totally defeatist" not to set a deadline.

In comments that were leapt on by Johnson, Hunt accused his rival of "peddling optimism" - to which the Tory leadership frontrunner responded: "I think we need a bit of optimism, frankly."

Asked if he would be prepared to suspend Parliament - also known as proroguing - in order to force through a no-deal Brexit, Hunt said: "When that has happened in the past, when Parliament has been shut down against its will, we actually had a civil war.

"I think it would be a rather curious thing to do, if this is about taking back control for Parliament, to actually shut it down."

He challenged Mr Johnson to rule it out, but the former London mayor said: "I'm not going to take anything off the table, any more than I'm going to take no deal off the table.

"I think it's absolutely bizarre at this stage in the negotiations for the UK - yet again - to be weakening its own position."

The debate follows a series of hustings around the UK for the candidates, including one in Scotland last Friday.

Conservative party members across the country have been receiving their postal ballots in recent days, with the result of the contest expected later in July.

What struck me watching tonight was what was missing.

I didn't hear the word Scotland, no talk of the union, no talk of a second independence referendum.

That seems striking to me, from two candidates who really have seemed over the last couple of weeks to be trying to boost their unionist credentials.

In terms of winning or losing, I suppose it was much more brutal than we might have expected it to be.

I think Jeremy Hunt did go on the attack, I think he did score some blows, particularly with that question to Johnson about whether he would resign as prime minister if he couldn't deliver Brexit by October 31.

But you start to think: does this really matter here?

The bluff, the bluster, the humour, what some might call the charisma of Johnson, does always seems to carry him through in these sorts of environments.

Jokes about 'hamster wheels of doom' get laughs from the audience. The audience did seem to be giving him more applause, particularly in the first half.

Will Hunt have picked up a few extra votes from Tory members after tonight's performance? Possibly.

Will it ultimately make a difference to the final result when so many members have already voted? Possibly not.