Dozens of Conservative MPs including a former Prime Minister, a former party leader and seven ex-Cabinet Ministers have backed a pledge not to support any new taxes on hard-pressed Britons.
The decision will be seen as a direct challenge to Prime Minister Rishi Sunak and Chancellor Jeremy Hunt, as Tory MPs and activists gather this weekend for the party's annual conference in Manchester.
Hunt is resisting renewed calls for immediate tax cuts, amid growing concern about the rising tax burden, while on Friday Treasury minister Andrew Griffith said it would not be “responsible” to rule out further tax rises.
The pledge not to increase taxes has been signed by 33 Conservative MPs enough to put any attempt to threaten any attempt to increase taxes at the Autumn statement or spring Budget.
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Former Prime Minister Liz Truss and former party leader Sir Iain Duncan Smith have signed up as well as seven former Cabinet ministers: Sir Jake Berry, Sir Brandon Lewis, Sir Jacob Rees Mogg, Dame Priti Patel, Sir John Redwood, Alun Cairns and David Jones.
John Stevenson, chairman of the Northern Research Group, Greg Smith, chairman of Conservative Way Forward and Danny Kruger, chairman of the New Conservatives have also signed.
Each MP signed the pledge which reads: "I (MP's Name) pledge to the taxpayers of (constituency) and to the British People, that I will not vote for or support any new taxes that increase the overall tax burden. My pledge will protect the working people, families and businesses of our United Kingdom."
The pledge is similar to the Taxpayer Protection Pledge, a written promise which legislators in America have been urged to sign up to since the mid-1980s.
Sir Jake Berry - who has organised the initiative - said he wanted prospective parliamentary candidates at next year's general election, members of the devolved administrations as well as peers to sign up.
Berry told GB News: "There is no such thing as government money, only taxpayers' money. For too long, we have seen the flawed political idea of taxing the economy towards health.
The UK tax burden under Rishi Sunak and Jeremy Hunt is reaching its highest rate since WW2PA
"Whilst we know this does not work, it continues to happen. Now is the time to take a stand and to make clear that this should not happen any longer.
"I believe in Britain and the British people; we must trust them to make decisions about their own lives.
"I want to see a low tax, high growth economy, and this cannot happen with further tax increases when they are already at a 75-year high."
Patel added: "We must be ambitious, reforming and bold to cut the tax burden on hardworking families and businesses so they can keep more of what they earn to support themselves and create growth in the economy.
"The Conservatives are the party of low taxes and economic freedom and staying true to those values will help us win the next General Election.”
A Treasury source told GB News: “The Prime Minister and Chancellor want to lower the personal tax burden, but inflation reduction has to be the priority right now."As Margaret Thatcher rightly said, inflation is the number one enemy. Our plan to halve inflation is working, so we must stick to it. The plan will work - we promise.”
Full list of Tory MPs who have signed the tax pledge: Sir Jake Berry, Sir Brandon Lewis, Rt Hon Liz Truss, Sir Jacob Rees Mogg, Dame Priti Patel, Sir Iain Duncan Smith, Sir James Dudderidge, Dame Andrea Jenkyns, Sir John Redwood, Danny Kruger, Greg Smith, Bill Wiggin, John Stevenson, Damien Moore, Ben Bradley, David Jones, Karl McCartney, Col Bob Stewart, Lucy Allan, Craig Whittaker, Robert Courts, Craig Mackinley, Alun Cairns, Stephen McPartland, Henry Smith, Kevin Foster, Paul Bristow, Chris Green, Adam Holloway, Nick Fletcher, Jonathan Gullis and Marcus Fysh.