The foreign secretary is expected to launch her bid with a pledge to reverse Rishi Sunak’s rise in national insurance, despite economists warning that the tax cuts proposed by the former chancellor’s rivals are “nutty” and potentially inflationary. Sajid Javid, Tom Tugendhat and Jeremy Hunt have all backed the highly controversial plan to put asylum seekers on one-way flights to Rwanda, with Mr Hunt saying he hoped “offshoring” could be extended to more Countries. Despite being seen as moderates by the party’s One Nation wing, Mr Tugendhat and Mr Hunt have also vowed to press ahead with Boris Johnson’s plan to rip up Brexit deals with the EU through the Northern Ireland Protocol Bill. Describing Brexit as a “revolution” that could not be reversed, Mr Tugendhat promised to ensure Northern Ireland was “fully and completely part of the UK single market”. Mr Hunt also backed the bill and suggested he regretted backing the Remain campaign – saying he would be “very tempted” to vote Leave if he could go back in 2016. He also said he would make a strong Brexit campaigner Esther McVey his deputy prime minister if he won the competition. It came as right-wing Brexit campaigner Suella Braverman sought to outdo her leadership rivals by promising to take the UK out of the “jurisdiction” of the European Court of Human Rights. The attorney general said it was “unacceptable” for the Strasbourg court to block the first attempted flight to Rwanda last month, although it is unclear whether she intends to withdraw the UK from its commitment to the European Convention on Human Rights. which the court oversees. Ms Truss is set to promise a reversal of Mr Sunak’s national insurance rise in April as part of a “low tax” promise set out in her official leadership presentation on Monday. Paul Johnson, head of the Institute for Fiscal Studies, said on Twitter that critics of the idea were right to point out that cutting taxes does not “magically” boost growth. But Tory rivals have pushed to outdo Mr Sunak, who has warned against “fairy tale” promises, with various pledges. Mr Javid claimed his plans to cut income and corporation tax worth £39bn a year would be fully funded, saying he would ask all departments to make savings. He promised to lay out the details in a “scorecard” in the coming days. Responding to Mr Javid and Mr Hunt’s plans to cut corporation tax to 15%, Torsten Bell, chief executive of the Resolution Foundation think tank, said: “This is crazy. We’re talking about £30 billion. This will be an expensive leadership election.” Labor described the increasingly tight contest as a “chaotic catwalk” as Tory MPs opposing Mr Sunack launched a so-called “dirty dossier” designed to stop building support for his campaign. The 424-word note shared on Tory WhatsApp groups pointed out that Mr Sunak had registered his campaign website in December and was “secretly” holding a US green card. He also disputed his explanation of his wife’s tax-free status, which was revealed by the Independent in April. A Tory source told the Independent that the memo shared by some MPs was part of a campaign among right-wing loyalists to Mr Johnson to stop the contest becoming a “coronation” for Mr Sunak. Sajid Javid ‘had no idea’ Rishi Sunak also wanted to quit at the same time However, the former chancellor’s campaign continued to build momentum as former ministers Simon Hart and Helen Whately backed him and pushed his tally of endorsements past 30, putting him ahead of the field. Grand Sapps appeared to attack the front-runner in an interview with The Sunday Times, saying: “I haven’t spent the last tumultuous years planning … I haven’t mobilized a leadership campaign behind his back.” And staunch Johnson ally Zach Goldsmith also attacked Mr Sunak over his record on the environment, although he denied any personal animosity towards the former chancellor. Lord Goldsmith claimed Mark Spencer – one of Mr Sunack’s senior campaign backers – had been lined up for a key role as environment secretary if the former chancellor wins the contest. “He will be our little Bolsonaro,” he said of Mr. Spencer. Mr Javid, who resigned from the Johnson government minutes before Mr Sunak on Tuesday night, denied conspiring with the former chancellor to get rid of the prime minister. Asked if he had agreed a resignation plan with Mr Sunak, the former health secretary told the BBC’s Sunday morning show: “Not at all. This was a decision I made.” Penny Mordaunt garnered a raft of endorsements after launching her campaign on Sunday with an unusually bombastic Twitter video. The Royal Navy reservist’s video featured images of soldiers and fighter jets played to rugby’s patriotic anthem ‘World in Union’. The footage raised eyebrows over a sequence showing Oscar Pistorius, the South African athlete found guilty of murder, alongside British Paralympic champion Jonnie Peacock. It was later reposted without the Paralympics sequence after Mr Peacock told her he had “officially asked to be removed from this video”. The Conservative Party’s 1922 Followers Committee, which sets the rules for the first stage of the contest, will set the exact timetable after a meeting on Monday. Bob Blackman, who is a member of the executive, said nominations will close on Tuesday afternoon, and there will be a process to whittle the candidates down to two finalists by July 21.