Suella Braverman said she struck a deal with Rishi Sunak during the leadership contest that paved the way to him becoming Prime Minister when his opponents dropped out.
In a scathing letter following her sacking as home secretary, Mrs Braverman told Mr Sunak he had “no personal mandate” to lead the UK after losing the 2022 Conservative leadership contest to Liz Truss.
But the Leave campaigner said, despite that, she agreed to serve in his Cabinet because of “firm assurances” he gave her “on key policy priorities” after Ms Truss’s premiership quickly unravelled.
Mrs Braverman said she agreed to come back as home secretary — having been forced out by Ms Truss — on “certain conditions”.
The right-wing politician said they included a commitment to reduce net migration into Britain and efforts to tackle international blocks on deporting those who arrive across the English Channel via small boats.
She said her support for him, as a result of their alleged backroom pact, helped him secure the keys to Downing Street.
Mrs Braverman told him that it was “generally agreed that my support was a pivotal factor in winning the leadership contest and thus enabling you to become Prime Minister”.
In her letter to Mr Sunak, published on X — formerly Twitter — on Tuesday: “As you know, I accepted your offer to serve as home secretary in October 2022 on certain conditions.
“Despite you having been rejected by a majority of party members during the summer leadership contest and thus having no personal mandate to be Prime Minister, I agreed to support you because of the firm assurances you gave me on key policy priorities.
“Those were, among other things:
“1. Reduce overall legal migration as set out in the 2019 manifesto through, inter alia, reforming the international students route and increasing salary thresholds on work visas;
“2. Include specific ‘notwithstanding clauses’ into new legislation to stop the boats, i.e. exclude the operation of the European Convention on Human Rights, Human Rights Act and other international law that had thus far obstructed progress on this issue;
“3. Deliver the Northern Ireland Protocol and Retained EU Law Bills in their then existing form and timetable;
“4. Issue unequivocal statutory guidance to schools that protects biological sex, safeguards single sex spaces, and empowers parents to know what is being taught to their children.”
She said the supposed deal amounted to “a document with clear terms to which you agreed in October 2022 during your second leadership campaign”.
The MP for Fareham went on to describe how she “trusted” him as Prime Minister to deliver on the alleged pledges, but that he had “repeatedly failed to deliver on every single one of these key policies”.
Mrs Braverman’s first spell heading up the Home Office under Ms Truss culminated in her effective dismissal for leaking confidential cabinet papers to right-wing backbencher Sir John Hayes, a long-serving MP reported to have significant sway over her.
A subsequent inquiry found she had sent confidential papers to her personal email account on a number of occasions.
But she was brought back as home secretary by Mr Sunak just days after she left office in what was reported to be a deal to ensure she would support his leadership campaign following Ms Truss’s resignation.
He became Tory leader and subsequently Prime Minister after his rivals, including former prime minister Boris Johnson and Penny Mordaunt, stepped aside.
Mr Sunak decided on Monday to dismiss Mrs Braverman as home secretary — her second sacking from the same role in 13 months — following a series of controversies.
In the days before being fired, Mrs Braverman had described rough sleeping as a “lifestyle choice” and refused to water down an opinion article for a newspaper in which she attacked the Metropolitan Police over its handling of pro-Palestinian protests.
Her position was taken by James Cleverly in a reshuffle, with his sideways move making way for former prime minister David Cameron — now Lord Cameron — to make a return to Government as Foreign Secretary.
Downing Street, in its reply to the former home secretary’s letter, thanked Mrs Braverman for her service but did not touch on her suggestion a deal had been done ahead of Mr Sunak entering No 10.
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