Jeremy Corbyn last night vowed to ‘surprise’ Boris Johnson with a no-confidence vote which could bring his premiership to an abrupt halt.
The Labour leader said his party would table the motion at a time of its choosing, with sources not ruling out making a dramatic move this week.
If Mr Johnson is toppled within the next four months, he would be the shortest-serving UK prime minister ever.
Without the support of the DUP, the Conservatives do not have a majority in the Commons.
Mr Corbyn tweeted: ‘Boris Johnson has won the support of fewer than 100,000 unrepresentative Conservative Party members by promising tax cuts for the richest, presenting himself as the bankers’ friend, and pushing for a damaging No Deal Brexit. But he hasn’t won the support of our country.
‘Johnson’s No Deal Brexit would mean job cuts, higher prices in the shops, and risk our NHS being sold off to US corporations in a sweetheart deal with Donald Trump.
‘The people of our country should decide who becomes the prime minister in a general election.’
Asked whether Labour will table a vote of no-confidence in the new prime minister, Mr Corbyn told the BBC: ‘We will table one when appropriate to do so. We’ll decide when that will be – it’ll be an interesting surprise for all of you.’
New Liberal Democrat leader Jo Swinson said: ‘Whether it is throwing people under the bus or writing a lie on the side of one: Britain deserves better than Boris Johnson.’