The race to be Britain's next prime minister

Boris Johnson has edged closer to a final face-off to in the contest to select Britain's new prime minister, as Conservative MPs battle it out for the top spot.

The leadership race was sparked by the resignation of PM Theresa May as part of her deal to drive Britain's exit from the European Union - Brexit - forward.

There are now five remaining Tory leadership candidates in the race. They will be whittled down to the final two over the course of three votes in the next 48 hours, meaning the choice facing Conservative Party members will be clear by Friday (NZT).

Johnson moved 80 votes clear of the chasing pack in Tuesday's second ballot of Tory MPs, then emerged unscathed from his first televised hustings event.

Stewart, meanwhile, almost doubled his support among Tory colleagues as he moved within touching distance of Jeremy Hunt and Michael Gove, and used the BBC hustings event to cement his place as the most radical alternative to Johnson.

There was speculation last night that Sajid Javid, who is now the back marker after the elimination of Dominic Raab in Tuesday's vote, could withdraw from the race to support Johnson and increase his chances of landing the coveted role of Chancellor - finance minister - in a future Johnson government.

Johnson has effectively booked his place in the head-to-head run-off after securing 126 votes from Tory MPs.

Stewart has 37 votes, just nine behind Hunt, who is in second place, and stood out from the four "stop Boris" candidates in the TV debate by promising to take a no-deal Brexit off the table in an at times eccentric performance.

There remains scepticism among Tory MPs that after refusing to cut taxes he can convince enough of his colleagues to back him all the way to the final two.

Rory Stewart, meanwhile, almost doubled his support among Tory colleagues as he moved within touching distance of Jeremy Hunt and Michael Gove, and used the BBC hustings event to cement his place as the most radical alternative to Johnson.

Hunt and Gove took aim at Stewart during the debate, drawing fire away from Johnson, while Javid was largely supportive of the former foreign secretary.

Unless Hunt, Gove and Javid do a deal that involves just one of them going forward to the final rounds of voting, Stewart, the bookies' favourite to reach the final two with Johnson, could make the leadership challenge an all-Old Etonian affair.

During a frequently chaotic BBC One debate hosted by Emily Maitlis, the five candidates who remain in the race faced questions from viewers on Brexit, tax and public services.

Johnson, who had faced criticism for refusing to take part in a Channel 4 debate on Monday, used his appearance to make the case for a deal or no-deal Brexit on October 31, and followed a game plan of allowing the other candidates to squabble among themselves.

Johnson said: "We must come out [of the EU] on October 31 otherwise we will face a catastrophic loss of confidence in politics.

"Politicians said they would honour the verdict [of the referendum] but three years on we still haven't left. We have already kicked the can down the road twice and I think the British people are getting thoroughly fed up."

He added: "Unless we get out on October 31, I think that we will all start to pay a really serious price."

Michael Gove said he was "angry" that Britain had not left the EU but "because I started this, I will finish it".

He said it was "entirely feasible" to leave by the current Article 50 deadline but stopped short of giving an outright guarantee that it would happen.

While Hunt, Gove and Javid all offered similar promises of leaving the EU by Hallowe'en if at all possible, Stewart stood out from the crowd by saying no deal was not possible because: "In the end, we're in a room with a door and the door is called Parliament, and I am the only person here trying to find the key to the door.

"Everybody else is staring at the wall shouting 'believe in Britain'."

The International Development Secretary, who took off his tie during the debate and stared at the ceiling at times, said Britain needed to leave as "quickly as possible" but politicians also owed the public "their trust" and so "I would not waste time pretending I was going to negotiate a new deal with Brussels."

Gove retorted: "You cannot simply re-present the same cold porridge for a fourth time and ask people to say that's what they want.

"We need to have a different approach."

Jeremy Hunt said that if there was no prospect of a deal by October 31 "I would leave" but he would want to avoid "the disruption of no deal" if it was a case of delaying by a short period.

He said he was, however, prepared to leave without a deal but "it should only be a very, very last resort".

Gove said he was "angry" that Britain had not left the EU but "because I started this, I will finish it".

He said he would delay Brexit again if a deal was close, and would "absolutely" make sure Brexit happened in 2019.

In a notable toughening of his stance, which was seen as a plea to supporters of Raab to give him their votes, Javid said a hard deadline was needed to "concentrate minds in Brussels".

He said: "We have got to learn from our mistakes. One of the mistakes we have made so far is by having this flexible deadline.

"If you don't have a deadline, you don't concentrate minds, and that also includes the minds of our European friends."