Boris Johnson says the Tories will 'kick the bucket' if Brexit is delayed again
Tory leadership favourite Boris Johnson will warn his party they will "kick the bucket" if the UK does not leave the European Union by 31 October.
The former Foreign Secretary will say there will be no way back for the Tories if they continue to "alienate" voters by failing to deliver Brexit.
Speaking as he launches his campaign to be the next Prime Minister, Mr Johnson will say he is the candidate to "unite this country and unite this society"
And he will tell his party that he is the person who can beat Jeremy Corbyn's "Marxist cabal" at the next general election.
The bookies' favourite to succeed Theresa May has been accused by his rivals of hiding from scrutiny since Theresa May announced she is quitting Downing Street.
But in a bid to build on his commanding lead among MPs, Mr Johnson will attempt to paint himself as the saviour of the Tories, who have seen their poll ratings tumble as a result of the Brexit deadlock.
He will say: "Now is the time to unite this country and unite this society, and we cannot begin that task until we have delivered on the primary request of the people; the one big thing they have asked us to do. After three years and two missed deadlines, we must leave the EU on 31 October.
"We simply will not get a result if we give the slightest hint that we want to go on kicking the can down the road with yet more delay.
"Delay means defeat. Delay means Corbyn. Kick the can and we kick the bucket.
"With every week and month that goes by in which we fail to deliver on our promise I am afraid we will further alienate not just our natural supporters but anyone who believes that politicians should deliver on their promises."
Taking aim at the Labour party, he will point out that he twice beat Ken Livingstone to become mayor of London as proof that he is an election winner.
He will say: "We cannot let them anywhere near Downing Street and I would remind you that the last time I faced an emanation of that Marxist cabal I defeated him when the Conservatives were 17 points behind in London. And we can do it again."
The launch came as new analysis of polling commissioned by The Telegraph claimed that Mr Johnson could secure a 140-seat majority for the Tories if he became leader.
A ComRes study shows that the proportion of voters who would back the Conservatives in a general election leaps from 23% to 37% under a hypothetical Johnson premiership.
Punched into the online Electoral Calculus tool, the findings suggest that Mr Johnson could secure 395 seats for the Tories compared to 151 for Labour.
In a further boost for the would-be Conservative leader, the paper also reports that three unnamed MPs who had publicly declared their support for rival Michael Gove are set to shift to backing Mr Johnson.