Conservative MPs are warning of a backlash after threats they could lose the whip if they vote against the abolition of the 45p tax rate, with at least 14 MPs publicly expressing concern about the plans to cut taxes and slash spending. Jake Berry, the Conservative party chair, sparked anger among colleagues on Sunday when he said MPs would be expected to back the tax measures or would no longer be allowed to sit as Conservatives. Asked on Sky’s Sophy Ridge on Sunday show if MPs would lose the whip for opposing the budget, Berry said: “Yes, correct. That is a decision for the chief whip but as far as I’m concerned, yes.” One Tory MP said Berry’s comments risked “breaking the dam” and forcing more MPs out into the open against the abolition of the 45p top rate of tax or against the wider idea of unfunded borrowing to pay for tax cuts. Another called it “very provocative and very silly”, saying it “gives colleagues an excuse to move in numbers, especially those in marginal seats”. At least 14 MPs have broken cover to criticise the plans, though many more are expressing private scepticism. The former levelling up secretary Michael Gove told Liz Truss to change course over some of her tax cuts or risk them being voted down in the Commons, saying her plans as they stood were “not Conservative”. Speaking at the party conference, Gove said he was “going to have a conversation within the party and the country” about what to do next, refusing to rule out voting against the budgetary measures. But rebel MPs will not get an opportunity to test support for the controversial measures for many months. No 10 is now understood to be planning a vote on the tax cuts in March, likely after a spring Budget. The only immediate legislation needed is on stamp duty and abolishing the national insurance rise, which Tory MPs will back. Other MPs have also hinted at a deep unease about spending cuts which ministers have suggested they need to balance tax cuts, including the former cabinet minister Damian Green. Julian Smith, the former chief whip, responded directly to Berry, saying: “The first job of an MP is to act in the interest of their constituents and in the national interest. We cannot clap for carers one month and cut tax for millionaires months later.” Green, the former cabinet minister who chairs the One Nation group of Conservative MPs, told a rally that the group had work to do to make the argument to change course, including on spending and levelling up. Green said the Conservative party should always be about “helping people make the most of opportunities whatever their background … I think that’s moral, right and I also think it’s a political no brainer. If we end up painting ourselves as the party of the rich and the party of the already successful, then funnily enough most people won’t vote for us.” He added: “If that takes strong voices being used over the coming months, then I and many colleagues in parliament will not be backward in using those voices. We are at the early stages of this discussion.” Others who have publicly urged a rethink include Northern Ireland select committee chair, Simon Hoare, and justice committee chair, Bob Neill. Richard Graham, the MP for Gloucester, said the plans had led to “an increase in our deficit, inflation and interest rates, very tough market reaction without OBR support and spending cuts to come. Government this week should push tax cuts for the best off into the long grass.” Steve Brine, a former health minister, wrote on Facebook that to cut the top rate of tax was “tin-eared and extremely politically naive … I know there are many here that would benefit from the reduced top rate who don’t want it and that speaks volumes”. Other MPs who reflected stirrings of backbench unease about the government’s mini-budget included the Ashfield MP, Lee Anderson, who said “the optics” were not good around the mini-budget. “People in this country voted Conservative for the very first time, and they’re still a little bit dubious about us. They lent their vote to us,” he told a fringe meeting while declining to answer a question about whether he would vote against the government’s plans. Another backbencher, Danny Kruger, said the government should not now “take an axe to public spending or benefits in order to balance the books … we need to be supporting families and communities”. A number of other MPs said they were deliberating over whether to go public with their criticisms, but most said they believed a U-turn would come before inflicting a defeat became necessary. One former cabinet minister said there was enough support in the party to vote to defeat the measures, but said they predicted the government would change course. An MP said Truss would realise that a U-turn was the only route to political survival. “She’s like a shark,” they said. “You don’t get through the last three administrations and come out on top the other side unless you’re willing to do whatever it takes to survive. She will realise the writing’s on the wall – the only question is how quickly.” Another Tory MP who is a member of the government said it was possible the administration could face a defeat on the budget and “find out the hard way what happens when an unstoppable force meets an immovable object”.