Isaac Levido, the man in charge of the Conservative general election campaign, did not hold back.
"Let me be clear," he briefed Tory MPs at a closed-door meeting last Monday: "Divided parties fail". A fat lot of good that did the prime minister.
The next day, 60 Conservative MPs voted, fruitlessly, for an amendment in defiance of the government's bill to keep the proposed Rwanda removal scheme broadly compliant with the law.
The revolt shrunk at the substantive "third reading" on Wednesday.
More than 40 of them caucused before the vote and pulled back from bringing down the bill, and probably themselves and the government with it. Only 11 rebelled.
Still, it was a stretch for the prime minister to boast "the Conservative Party has come together" at a specially convened news conference the following day.
Sources informed Sky's political editor Beth Rigby that several "letters had gone in" from Tory MPs demanding a vote of no confidence in Sunak.
Such behaviour prompts the question: "Do the Conservatives have a death wish as a party of government?" To put it another way: "Do they sincerely want to win the next election?"
The public notices when a party is divided. The latest figures for December are Conservatives divided 70%, united 8%.
The polling company YouGov runs a survey tracking that issue for the Conservatives. The jaws of disillusionment sprung wide in January 2022, the height of the "partygate" revelations, and have stayed gaping wide ever since.
Labour's large lead in the opinion polls has also been in place for the past two years.
Two YouGov polls in the past week suggest that, if anything, it is getting bigger.
A large survey in key constituencies, commissioned by a newly formed right-wing faction calling itself the Conservative Britain Alliance, plotted the party on course to lose 196 seats, down to just 169 MPs to Labour's 385.
Next the regular monthly poll for The Times, conducted this week, gave Labour an increased lead of 27 points in voting intention, 47% to 20%, with Nigel Farage's Reform in third place on 12%.
In such dire circumstances, the prime minister at least is now sticking to Isaac Levido's advice and claiming that the Conservatives are united.
He is only managing to keep them together by constantly shifting closer to the position of the rebels on the right. He has declined to punish, or remove the party whip, from those who voted against the government on the Rwanda bill.
Instead, Sunak confirmed this week that he will order civil servants to ignore last-minute, so-called "pyjama orders" from the European Court of Human Rights (ECHR) under Rule 39, to halt deportations.
He and his ministers have adopted the nativist rhetoric of describing the ECHR as a "foreign court". The UK has been a founder member of the international court since 1959 and a Briton sits as one of its judges. It is not an EU institution.
Some of the rebels are veterans of the post-referendum Brexit deliberations which brought down Theresa May. Whatever moves she made in their direction were never enough.
Others, like Lee Anderson, were elected in 2019 on Boris Johnson's coattails. Bathetically Anderson abstained in the final vote because he couldn't stand the mockery from Labour when he entered the "nay" voting lobby.
That was a momentary weakness. The rebels have no interest in compromise and are already pressing for the UK to withdraw from the ECHR come what may, placing this nation alongside Russia and Belarus in Europe.
The prime minister claims that his Rwanda plan is the "will of the people". It was not in the Conservative Party's manifesto in 2019, although Boris Johnson subsequently floated the idea.
A majority of the general public, 53%, say it wouldn't "be effective". 40% want it abandoned, compared to 37% who say press ahead.
The cross-Channel migrants are a dramatic manifestation of people coming into the UK but are only a fraction of the record net total, over 600,000 a year, currently coming into the UK.
By common admission the number who would be sent to Rwanda, if the scheme were established, is smaller still. Sunak's "Stop the Boats" policy is almost a diversion from the complex issues raised by mass migration.
Sunak is drawing attention to Labour saying it would scrap the Rwanda scheme "even if it was working". He is continuing to tell voters that Labour has no plan, whatever policy they develop. As yet this does not seem to be damaging either Starmer or his party.
But 46% of Conservatives voters in 2019 said the Rwanda scheme would be effective, even more of them, 63%, want the government to continue with the policy.
In truth, Sunak appears more concerned with keeping the majority of his electoral base together than delivering "the will of the people".
Immigration is a major concern for some voters, but all categories and classes say the economy and cost of living matter more to them.
Here again, Conservative MPs are divided and feuding among themselves, with constant demands that the prime minister and Chancellor Jeremy Hunt go further with tax cuts than they feel the country can afford.
The Budget on 6 March will be a test of whether they resist or succumb to this pressure.
Many Tory MPs think their "narrow path" to election victory is all but disappearing. As such winning has ceased to be a priority. They are more interested in what happens to their party and their own careers after a defeat.
At least 54 of them have given up and are retiring. Those shouting loudest about the threat from Reform want to drive party policy in Farage's direction.
Farage appears to be more popular than Sunak with the ageing party membership who will choose the next Conservative leader but he is not eligible to stand.
Braverman, Jenrick, Badenoch and others are already positioning themselves for the vacancy which they think defeat will create.
Those on the other, One Nation, side of the party, and who managed to survive the Johnson era purges, are loyal but out of sympathy with the direction in which it is moving. They do not expect to win the next election.
Some feel that the Conservatives will need to elect another extremist as leader, and lose again, before they can "get their party back " - as Labour's Neil Kinnock once put it.
Interestingly, the new roster of Conservative MPs is likely to be more moderate, given the preponderance of centrist new candidates now being selected, coupled with the likely defeat of many "red wall" Tories.
Sunak is hoping to stay in power at least until the autumn. Before then the Conservatives face parliamentary by-elections in Wellingborough and Kingswood and probably Blackpool North.
All will be tough to hold on to the party's recent electoral form. Then there are the local elections in London and elsewhere. Such tests are as likely to divide as unite his party behind him.
Something may turn up. Labour needs a record swing to form a majority government and nobody, least of all Keir Starmer and his team, expect they will do as well on election day as in current opinion polls.
Still, as things stand, Issac Levido's warning and the Conservatives' dismissive reaction to it, may well be written into a chronicle of a political death foretold.