Sunak, who currently has the most support among MPs in the Conservative leadership contest, sought on Sunday to reassure eurosceptic Tories that he would take a hard line on Brexit and “capitalize on the freedoms” it offered. But Johnson’s supporters are determined to stop Sunak, who they say has betrayed the prime minister, and are now mounting an ongoing information campaign against him. Many are backing Liz Truss, the foreign secretary, who is struggling to gain momentum as the leadership race enters its final parliamentary stages. This week, Tory MPs will vote to finalize a two-person shortlist from which party members will then choose the winner. Johnson’s successor will be announced on September 5. A minister close to Johnson claimed Sunak would change policy on the Northern Ireland Protocol – a key part of the prime minister’s Brexit deal with the EU outlining the region’s trade status – and seek a compromise with Brussels to moderate the financial damage caused by the dispute. The minister said: “Rishi will want to do a quick deal with the EU and move on.” The minister also suggested Sunak would take a softer line with Russian President Vladimir Putin over his invasion of Ukraine because of the former chancellor’s concerns about the economic impact of the war. That claim was flatly denied by Sunak’s team, which said it had “led the way” in imposing sanctions against Moscow. A Johnson ally said Sunak last year opposed Johnson’s proposals to unilaterally ease border controls on goods arriving at Northern Ireland ports from mainland Britain by triggering Article 16 of the protocol, which allows some of the requirements to be suspended of. “We would have triggered Article 16 last year and [Lord David] Frost would not have resigned if Number 10 had his way,” the ally added, referring to the former Brexit minister who quit last December. “Rishi objected to the financial impact, which meant we just couldn’t do it.” The government is now pushing legislation through parliament that would override key parts of the Northern Ireland protocol. Sunak has said he will stick with the bill. Sunak’s allies said Johnson was also nervous about using the “nuclear option” of triggering Article 16 of the protocol last December, and the cabinet agreed it was the wrong time to escalate the row with Brussels. The European Commission has blocked British scientists from participating in the EU’s €95bn Horizon research program in retaliation and has previously warned that if the UK unilaterally rewrites Johnson’s Brexit deal, it risks sparking a trade war with the bloc. But the UK government has said the protocol undermines the 1998 Good Friday Agreement that ended three decades of conflict in Northern Ireland, and some businesses have complained of unnecessary red tape. Boris Johnson and Rishi Sunak: Johnson’s backers are determined to stop Sunak taking the top job © Andrew Parsons/10 Downing Street Johnson’s allies have repeatedly attacked Sunak, variously calling him a “traitor” and a “snake” after he became one of the first members of the government to resign this month in protest at the prime minister’s leadership. “Boris blames Rishi for the downfall of his prime ministership,” said a Johnson supporter. “It is infidelity of the highest order.” Sunak tried to defuse the row with the outgoing prime minister by praising Johnson’s achievements, but faced escalating attacks from rival factions of the leadership candidates. The former chancellor, who secured the support of 101 Tory MPs in the latest round of voting last week, is widely expected to make the final list of two to be presented to party members. Sunak knows some campaigners in the party are suspicious of his tax hikes, alleged disloyalty to Johnson and Brexit, despite the former chancellor – unlike Truss – voting to leave in the 2016 referendum. “I firmly believe I made the right decision by backing Leave,” Sunak wrote in the Sunday Telegraph, adding that the UK would be better off outside the EU with its “low growth and bureaucratic mentality”. He said that as prime minister he would create a Brexit delivery department and that by the next general election he would have “rejected or reformed all the EU legislation, red tape and red tape that is still in our statute book and slowing economic growth”. . But Jacob Rees-Mogg, the Brexit opportunity minister and a Johnson ally, who last week branded Sunak a “socialist” over his tax hike, claimed the Treasury was not so keen to scrap her law EU while he was chancellor.

Lucy Fraser, the Chancellor of the Exchequer, said in a letter obtained by Bloomberg that it was not possible to simply overturn the retained EU law – or Reule – which has been an integral part of British tax policy for four decades. He added in the letter written last month that he continued to have “significant concerns about ending Reul’s taxation entirely.” Rees-Mogg said: “Rishi’s position has changed quite quickly, but changes in repealing EU law are always welcome.” A spokesman for Sunak’s campaign said: “The former chancellor and the Treasury were fully behind the goal of removing Reul, it was a matter of the best mechanism to do that.” The Treasury wanted specific legislation to repeal Reul, in the form of future funding bills. Meanwhile, some Tory MPs believe former equalities minister Kemi Bandenos, currently fourth in the leadership race after last week’s vote, will end up backing Sunak. Badenoch clashed throughout the contest with Trade Secretary Penny Mordaunt, currently runner-up, mainly on the issue of transgender rights. Mordaunt has been accused of advocating gender self-determination while she was minister responsible for politics. She herself has denied it. Some Tory MPs believe Badenoch is trying to stall Mordaunt to help Sunak because he would rather be in the final two with Truss, currently third in the leadership contest. Badenoch denied this and said they were in the race “to win it”.