The Lib Dems and Change UK are continuing to oppose Jeremy Corbyn as caretaker PM despite the Greens, SNP, Plaid Cymru and even Ken Clarke supporting the plan.
Nicola Sturgeon said she would support the Labour leader as a candidate for caretaker prime minister, though added she was “open minded” about who takes on the role.
The Scottish first minister said she supports the Labour plan of bringing down Boris Johnson with a vote of no confidence and then securing a Brexit extension before an immediate general election.
But Labour would need vast cross-party support for the move to work, including from those among the Lib Dems’ 18 MPs, the Independent Group for Change (IGC) and the 21 exiled Tories.
Lib Dem leader Jo Swinson has called Corbyn unfit to govern, and a party spokesman made clear that they do not believe he can win the backing of the Commons.
“The question of whether or not we would support Corbyn in an emergency government is futile. He does not command the support of the House,” a spokesman said.
“Liberal Democrats are clear that we need to bring people together and find a candidate that can command the support of the House, and to push this disgraceful Conservative Government out of office.”
IGC leader Anna Soubry told PA she was “disappointed” with the SNP for expressing their support, and pointed towards suggestions that expelled Tory veteran Ken Clarke should take on the role.
“It’s being made very clear to Jeremy Corbyn that he won’t be in Number 10 with the support of myself and [the four other IGC MPs] or the Liberal Democrats.”
Corbyn called in August for a no confidence vote followed by a temporary government under his leadership to secure an extension to Article 50 and then a general election.
Plaid Cymru and the Greens are willing to back Corbyn.
Plaid MP Jonathan Edwards said: “Our priority is to stop a disastrous crash out Brexit and to deliver a referendum, we will seek to work with anyone willing to do so.”
Green MP Caroline Lucas reiterated her support earlier this week. She said: “He’s leader of the opposition and I think he has every right to expect to be interim prime minister… I think we need to come together,”
Last month Tory rebel Ken Clarke signalled his support for Corbyn.
He said: “So long as it were absolutely certain we could keep Jeremy under control and he wouldn’t have the slightest chance of implementing any bits of his Labour manifesto, I hate to tell you but I probably would.”