The race to become <a href="https://www.thenationalnews.com/world/uk-news/2022/07/06/boris-johnson-defies-pressure-no-i-will-not-go/" target="_blank">Britain’s next prime minister is likely to descend into acrimony</a>, with some analysts suggesting it could become “the dirtiest in history”. After the resignation of <a href="https://www.thenationalnews.com/opinion/comment/2022/07/07/i-got-on-well-with-boris-and-i-hope-one-day-britons-rediscover-why-they-liked-him/" target="_blank">Boris Johnson</a> last Thursday, it is expected that up to 16 Conservative MPs could stand in the race to become next leader. There is now intense pressure on candidates to promote their positions, as voting could begin as early as Tuesday. But rumours persist across Westminster that dossiers on the candidates have already been compiled containing claims of extra-marital relationships, compromising photographs and emails. “There are daggers drawn between people across the various tribes of the party and they’re willing to yield them,” one Tory insider said. “This could well become one of the dirtiest leadership campaigns in our history.” Newly appointed Chancellor Nadhim Zahawi has already been forced to issue a statement after complaining about being the victim of a smear campaign. On social media on Sunday evening, he strongly denied claims that he had been under investigation by criminal authorities and the HMRC. Mr Zahawi said if he became leader of the Conservative Party, he would publish all future tax returns. “There have been news stories over the last few days which are inaccurate, unfair and are clearly smears," Mr Zahawi said. "It’s very sad that such smears should be circulated and sadder still that they have been published. “These smears have falsely claimed that the Serious Fraud Office, the national crime agency, and HMRC are looking into me. "Let me be absolutely clear. I am not aware of this. I have not been told that this is the case. "I’ve always declared my financial interests and paid my taxes in the UK. If there are questions, of course, I will answer any questions HMRC has of me. “And I will go further to reassure colleagues and the wider public. I make a commitment today that, if I am prime minister, I think the right thing to do is for me to publish my tax return annually. “There have been claims I benefit from an offshore trust. Again, let me be clear, I do not benefit from an offshore trust. "Nor does my wife. I have never been a non-dom, my wife has never been non-dom, she’s never used offshore status, or a company to avoid tax. "I have never used offshore companies or services firms based in tax havens for the purchase of property or properties in the UK. “I have only been resident of one country since arriving in the UK as an 11-year-old. I have never sought tax status in any country other than the UK. “I’ve answered these supposed allegations because I think the right thing to do is to be transparent. I have corrected the record. I trust these smears will now be seen for exactly what they are.” Reports have also already surfaced on <a href="https://www.thenationalnews.com/world/uk-news/2022/07/07/suella-braverman-tells-boris-johnson-to-quit-and-says-she-wants-to-be-next-prime-minister/" target="_blank">the candidate Suella Braverman</a>’s association with a controversial Buddhist order, the founder of which faces allegations of sexual misconduct. Rishi Sunak, the former chancellor, has become an early favourite with potentially 80 MPs backing him. But this has also made him a target for other contenders and their factions, with Downing Street being forced to deny it has been briefing against him. There is anger among Mr Johnson’s supporters, who accuse Mr Sunak of treachery for resigning on Tuesday evening, triggering the cascade of more than 50 MPs quitting government. But Mr Sunak could unite several wings of the party as an original Brexiteer rather than a convert, who resigned on principal and handled the economy competently through the Covid-19 pandemic. The threat from his challengers will become clear in the next 24 hours, as candidates hurriedly declare in time to make a mark and before balloting begins. By late on Sunday, 11 MPs had put themselves forward as the next prime minister, with Penny Mordaunt, Liz Truss and Rehman Chishti the latest. The former first female defence secretary, 49, opened her campaign with a well-honed video and the headline: "Leadership has to change." "It needs to become a little less about the leader and a lot more about the ship," the Trade Minister said. The Foreign Secretary Liz Truss pledged to reverse the controversial national insurance hike if made Tory leader, as she insisted she can be “trusted to deliver”. The senior Cabinet minister, who along with Ms Mordaunt will be the biggest threat to Mr Sunak, promised to “start cutting taxes from day one” to help with the cost of living. Mr Chisti, the newly appointed Foreign Office minister, made an even unlikelier bid for the Tory leadership on Sunday evening in a video posted on Facebookthe latest. <a href="https://www.thenationalnews.com/world/uk-news/2021/08/27/tom-tugendhat-this-is-what-defeat-looks-like/" target="_blank">The more liberal Tom Tugendhat</a>, 49, a former army officer who served in Iraq and Afghanistan, is the leading "One Nation" Conservative candidate. He made strong headway after strident Brexiteer Anne-Marie Trevelyan, the International Trade Secretary, backed him. The tax-cutting current Mr Zahawi, 55, could well attract a significant chunk of the Johnson loyalists, with Lord Zac Goldsmith, the prime minister’s close ally, publicly supporting him. Potentially less of a threat will be Jeremy Hunt, who is presenting himself as the mature, clear-headed contender who represents a complete break from Mr Johnson. Grant Shapps, the Transport Secretary, and Sajid Javid, the former health secretary, have promised to cut taxes, while Kemi Badenoch, an ardent right winger, will be expected to draw much media attention. <a href="https://www.thenationalnews.com/world/uk-news/2022/07/05/what-is-the-role-of-the-1922-committee-in-deciding-boris-johnsons-future/" target="_blank">The 1922 Committee, comprised of backbench MPs, will decide on election rules</a> on Monday. It will seek to eliminate contenders quickly by setting a high number of votes that each MP requires to reach subsequent balloting rounds. It plans to complete parliamentary party voting before Parliament's summer break on July 21, when the remaining two candidates will campaign for several weeks to win the votes of the 200,000 Tory party members. A new prime minister could be installed by late August. In 2019 several candidates pledged to conduct a “clean campaign” that would not cause lasting “blue on blue” damage to the Conservative Party, which in a recent poll was 11 points behind Labour. Former party leader William Hague said the country needed “calm reflection” after several years of turmoil. "Conservatives should be careful not to spend their time undermining some of their own leading figures," Mr Hague said.