Boris Johnson could soon be forced to stand down as prime minister to make way for Jeremy Corbyn

• Boris Johnson could soon be removed from office under a plan being pushed by opposition parties.
• Johnson's opponents fear that he will find a way of forcing Britain out of the EU without a deal next month.
• The Scottish National Party now believe the only way to prevent this happening is to make Labour party leader Jeremy Corbyn a caretaker prime minister.
• Under the plan Corbyn would become prime minister for a few weeks in order to delay Brexit and call a general election.
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Boris Johnson could soon be forced out of office, in order to make way for Labour party leader Jeremy Corbyn to become prime minister. Here's why.

The UK prime minister is currently the leader of a minority government, following the defection of one former Conservative MP to the Liberal Democrats and Johnson's own decision to expel 21 members of his own party.

Johnson's advisers originally believed this would only be temporary and that opposition parties would swiftly vote for a general election, which some polls suggest he would win.

However, the opposition has other ideas and are currently blocking a general election until Brexit has been delayed beyond its current deadline of October 31.

Boris Johnson is running out of road

This presents a problem for the prime minister, who insists that he will not delay Brexit, despite members of Parliament passing a law instructing him to do so. 

This means that Johnson may ultimately have little choice but to resign. However, allies of Johnson are briefing that he will take a different course and find some way of circumventing the Brexit delay law.

Former Conservative prime minister John Major warned on Thursday that this is exactly what Johnson is planning.

As a result, the UK's opposition parties are growing nervous and believe they may have to act first in order to prevent Johnson finding some method of forcing Britain out of the European Union next month.

The caretaker prime minister 'has to be Corbyn'

The Scottish National Party, which is the UK's third-largest party, now believes that the only surefire way to prevent Johnson forcing through a no-deal Brexit is to remove him from office and replace him with Jeremy Corbyn as a caretaker prime minister.

Under the plan, Jeremy Corbyn, who is the leader of the second-largest party in parliament, would briefly enter Downing Street with the sole purpose of delaying Brexit, before triggering a general election.

Responding to a tweet on Friday suggesting that opposition parties should temporarily install Corbyn as prime minister, the Scottish First Minister Nicola Sturgeon replied: "Agree with this," adding that "Nothing is risk free but leaving Johnson in post to force through no deal - or even a bad deal - seems like a terrible idea to me."

One senior SNP source told ITV's Robert Peston that Corbyn would be the only realistic choice for the role.

"It is increasingly clear that we will have to install a new prime minister via a vote of no confidence so that we can request a delay to Brexit and hold an election," the source said.

"The convention is absolutely clear that it is the leader of the opposition - in this case, Jeremy Corbyn - who should become prime minister in those circumstances.

"Trying to find a compromise candidate, a national unity candidate, is too complicated, especially in the time we have. Whether people like it or not, the temporary prime minister has to be Corbyn."

Johnson's opponents see Corbyn as a lesser risk

Winning a vote in the UK Parliament to make Corbyn prime minister looks tricky, however. Even with the SNP's support, Corbyn would still need the votes of all other opposition parties as well as a significant number of former Labour and Conservative MPs in order to become prime minister.

Given that some of those former Labour MPs left the party specifically because of their opposition to Corbyn, this looks like a very difficult task. The UK's fourth-largest party, the Liberal Democrats, are also reluctant to install Corbyn, even for a short period, with their leader Jo Swinson describing him as "unfit" to be PM.

However, time is running out to prevent a chaotic exit from the EU.

And if push comes to shove, Johnson's opponents may ultimately decide that a few weeks of the Labour leader in charge, is less risky than allowing the current prime minister to remain there any longer.

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