Nadine Dorries has warned Tory MPs not to “foist” another prime minister on the public who they did not vote for.
The former culture secretary and key ally of Boris Johnson said replacing yet another leader would be a “totally untenable position”.
Dorries urged her colleagues to “back” Truss after she came under fresh pressure following a bruising clash with the 1922 committee of backbench MPs last night.
Dorries, who supported Truss for the Tory leadership but has since been among her critics, said the MPs who had been circulating a “smorgasboard” of names to replace her “are not taking into account the fact that they cannot foist upon the British public another prime minister that the public have not voted for”.
Dorries’ comments take a different tone to the criticism she has levelled at Truss in recent weeks.
Last week, the former Cabinet minister warned the Tories would face a “complete wipeout” if there was a snap general election, saying: “We don’t need a disruptor, we need a unifier.”
She also accused Truss’s government of “lurching to the right” and leaving the door to the centre ground “wide open” for Labour leader Keir Starmer.
Last night Tory MPs were openly talking about replacing Truss with a new leader after she failed to get her backbenchers behind her tax-cutting programme at the 1922 gathering last night.
One MP told HuffPost UK that Truss was “crap” and that the atmosphere was “pretty flat” in the room.
“Even the whips couldn’t be bothered getting people to ask supportive questions.”
Former minister Robert Halfon told Truss she had “trashed blue collar conservatism” by weakening the government’s commitment to affordable housing and lifting the cap on bankers’ bonuses.
Another MP said: “I would say it was worse than anything Theresa May ever faced when she was leader.”
Paul Goodman, the editor of the influential ConservativeHome website, suggested there had been speculation that Truss could be replaced with a joint ticket involving her former leadership rivals Rishi Sunak and Penny Mordaunt.
Goodman, a former Tory MP, told BBC Radio 4′s Today Programme: “All sorts of different people are talking about all sorts of different things because the Conservative backbenchers are casting around for a possible replacement for Kwasi Kwarteng, even for a possible replacement for Liz Truss.
“All sorts of names are being thrown about, Rishi Sunak, even Boris Johnson, Kit Malthouse, Sajid Javid.
“But one idea doing the rounds is that Penny Mordaunt and Rishi Sunak, who, after all, between them got pretty much two-thirds of the votes of MPs, come to some kind of arrangement and essentially take over.”
Today Truss ally James Cleverly also warned that removing Truss would be “disastrous”.
Cleverly told BBC Radio 4’s Today programme: “We have got to recognise that we do need to bring certainty to the markets.
“I think changing the leadership would be a disastrously bad idea politically and also economically.
“We are absolutely going to stay focused on growing the economy.”