Boris Johnson is poised to become Conservative leader on Tuesday with senior MPs in open revolt against his threat to take Britain out of the European Union without a deal.
Alan Duncan resigned as a foreign office minister on Monday to seek a Commons vote that could have prevented Mr Johnson from becoming prime minister. Mr Duncan said he could not serve under Mr Johnson, whom he has previously described as a "circus act", and asked speaker John Bercow to test whether the former foreign secretary would command the confidence of the House as prime minister.
“This is the first time in our parliamentary history that the prime minister of a minority government has changed mid-term. Thus the normal assumption that succession is automatic cannot be said to apply, and his ability to command a majority in the House should arguably be tested before the prime minister can safely advise the queen who should succeed her,” Mr Duncan wrote in a letter to Mr Bercow.
The speaker rejected the call for a pre-emptive confidence vote ahead of Mr Johnson's expected move into Downing Street on Wednesday afternoon. Three cabinet ministers have said they will resign if Mr Johnson becomes Conservative leader and others are expected to follow suit.
Mr Johnson has said he will ask all members of his cabinet to pledge support for his policy of leaving the EU on October 31st, with or without a deal. But former prime minister Tony Blair said he does not believe Mr Johnson will take the risk of pursuing a no-deal Brexit against the will of Parliament.
“My strong belief is that Boris Johnson will not dare try to take Britain out with no deal when Parliament will have voted against it and with no endorsement from the British people. I mean you’d be more than reckless to take that risk,” Mr Blair told The Irish Times.
Mr Blair said that for Ireland, abandoning the backstop would mean accepting the inevitability of checks on the Border because Mr Johnson is determined to take Britain out of the single market and the customs union. He said Mr Johnson was peddling false hope in suggesting that he can persuade the EU to abandon the backstop.
"Hope is good but false hope is not good. If you've studied the detail of this, you must know that what he's saying at the moment can't be negotiated with Europe. I mean, just imagine the European summit. He turns up and Europe says 'Okay we're selling the Irish down the river now'. I can't see it," he said.
Two other former prime ministers, John Major and Gordon Brown, also warned Mr Johnson against pursuing a hardline Brexit policy. Sir John said Mr Johnson must be a prime minister for all and not just for "an ultra-Brexit faction". And Mr Brown said that millions of people who voted for Brexit do not want Britain to leave the EU without a deal.
"Even if some of the immediate chaos forecast by officials is averted on the day, the long-term economic impact of no-deal Brexit is where the calamity lies. British history includes self-inflicted wounds – military disasters such as the Charge of the Light Brigade and the fiasco of Gallipoli – but no peacetime act of self-harm can rival a no-deal Brexit for which we are so woefully unprepared," Mr Brown said.
Voting closed in the Conservative leadership election on Monday afternoon and the new leader will be announced at 11.45am in central London. If Mr Johnson wins, as all polls and pundits predict, he will become prime minister on Wednesday afternoon.