It’s not often that a one-word post on X can sum up the mood of an entire parliamentary party, but it happened this week.

Within minutes of prime minister’s questions ending on Wednesday, former cabinet minister Simon Clarke took to the platform formerly known as Twitter and simply said: “Iceberg.”

That was a reference to an interview he gave to the BBC in January when he warned that the Conservatives were heading for disaster under Rishi Sunak.

“No one likes the guy who’s shouting ‘iceberg’,” Clarke said. “But I suspect that people will be even less happy if we hit the iceberg. And we are on course to do that.”

If anything, things have got worse for the Tories in the intervening two months, with the past seven days encapsulating the miserable situation in which the prime minister finds himself.

On Monday, the worst kept secret in Westminster was confirmed when Lee Anderson – until January a Tory deputy chairman, no less – announced that he was defecting to Reform UK.

That led to another round of Conservative blood-letting, with one Tory insider telling HuffPost UK that Sunak had “literally given Anderson” to the right-wing party by suspending him over his attack on Sadiq Khan.

Even worse was to follow, with Downing Street providing a textbook example of how not to handle a political crisis in their response to revelations that the Tories’ biggest donor, Frank Hester, had said Diane Abbott made him “want to hate all black women” and “should be shot”.

Ministers were initially sent out to defend Hester – who has given the party £15 million in the last year – and instruct the country to simply “move on”.

But as the political pressure grew – and after Kemi Badenoch had broken ranks – No.10 bowed to the inevitable and announced that the PM did indeed believe that the remarks were “racist and wrong”.

In an attempt to regain control of the political narrative, Sunak finally put an end to the feverish speculation by finally announcing on Thursday night that the general election will not be held on May 2.

There are few Conservative MPs, however, who do not believe that this will just be a stay of execution for their party, which continued to languish 20 points behind Labour in the opinion polls.

“The death march has begun,” one former cabinet minister told HuffPost UK.

The next political flashpoint for the prime minister comes in less than seven weeks, when local elections take place in England and Wales.

No one expects them to be anything other than catastrophic for the Tories, who face losing around half of the council seats they currently hold.

One senior Conservative MP said Sunak was “certain” to face a leadership challenge in the aftermath, with no guarantee that he will survive.

“Kemi, Penny, Grant, Shapps, Jenrick and presumably others are all on manoeuvres, either to take over now or after the election,” he said.

A former minister said he believed enough letters will be submitted to Sir Graham Brady, chair of the 1922 committee of backbench Tories, to trigger a vote of confidence in his leadership.

“This feels like the week where it’s started to fall apart completely,” he said.

“But that’s good because it’s been needed to to get people to do something – there is no outcome other than total disaster if we don’t change course.

“The day after the local elections, Rishi will have to explain to people how we can still win a general election five months later, and I don’t think he can.

“The letters of no confidence are already going in, and we only need 52 to trigger a vote. There are then two scenarios; either the PM decides not to contest it and goes gracefully, or he does contest it and he performs very badly.”

Some MPs believe that, if the 1922 Committee is amenable, the party’s rulebook could be changed to allow a leadership election to be wrapped up quickly, with Tory members voting online and a new PM in place by June.

“You would then need to proceed to a general election very quickly, either in July or September,” said one backbencher.

Some Tories mutter darkly about the party being reduced to just 100 MPs after the next election unless drastic action is taken.

And while they don’t seriously believe a new leader can win the election, they think he or she could at least save enough seats to make the Tories competitive again when the next one comes along.

One MP said: “We all love the Conservative Party and it could just die. It really is that serious because if we go down to the sort of numbers we are talking about, we could be eclipsed completely by another party on the right.

“It really is decision time, and it feels like there are enough people now to make it happen.”

Adding to the dark mood in the Conservative parliamentary party is the fact that the Budget, in which Jeremy Hunt slashed another 2p off National Insurance, has failed to give the party any opinion poll bounce at all.

One ex-minister said: “I was in the chamber for it and it was so lacklustre. How could the chancellor expect to win over the country when he couldn’t even win over his own MPs?”

Next week will see Sunak’s flagship Rwanda bill return to the Commons, and Downing Street hope that getting that onto the statute book will finally lead to deportation flights taking off to the east African country and a much-needed political win for the embattled PM.

But with the mood among the PM’s parliamentary colleagues so gloomy, and the opinion polls refusing to shift, it seems highly unlikely to be enough to save Sunak’s political career.

Whether it’s at the hands of his MPs or the voters, his time at the helm of the government is coming to an end.