His attack came as a new poll of Tory party members gave Truss a commanding lead in the race to become prime minister. Taxes and spending have become the key battleground in the bitter fight, with Sunak insisting that immediate tax cuts, as Truss has promised, would risk exacerbating the cost-of-living crisis. The YouGov poll of Tory members published on Thursday put Truss ahead by 62% to 38%. With ballots expected to be cast in the coming days, candidates will take part in 12 inductions across the country before the result is announced on September 5. Sunak has repeatedly portrayed himself as the candidate who wants to have a “grown-up conversation” about the economy instead of telling what he has dismissed as “fairy tales.” Asked about the impact of Truss’ tax cut plans, Sunak said: “Yes, I think it would be inflationary.” With inflation already at a 40-year high, he told LBC: “My strong view is that if the government goes on a massive borrowing spree, it will only make things worse. And that will mean the problem will last longer.” He pointed to the potential impact on homeowners, saying: “It will raise their mortgage rates if interest rates have to go very high to deal with it.” The Trust doubled down on its insistence that its tax cut plans – which include reversing the recent rise in national insurance and canceling the rise in corporation tax – were affordable and would “reduce inflation”. Labor insisted neither candidate would offer a fresh start after 12 years of Conservative government. Shadow chief secretary, Pat McFadden, said: “Both Rishi Sunak and Liz Truss offer more of the same. They are the next candidates. Neither has a plan to deal with our stagnant economy – in fact, they have both presided.” Daisy Cooper, the deputy leader of the Liberal Democrats, said: “While Rishi Sunak and Liz Truss are at odds with each other, people are suffering because of the tax increases they have brought about. We are stuck with a zombie government and ministers who are focused on the leadership campaign rather than doing their jobs.” Analysis by the Institute for Fiscal Studies (IFS) showed that the Trust’s promises were ultimately likely to lead to cuts in public spending. “They will mean higher borrowing or less public spending or some combination,” it said. Responding to Truss’ suggestion that she could rewrite the government’s fiscal rules to pave the way for more spending, the IFS analysis added: “In this context it is always important to remember that, whatever set of fiscal rules is chosen to be imposed from herself. in the short term, ultimately lower taxes mean lower spending.” Former Conservative chief secretary to the Treasury David Gauke said he was concerned about Truss’ plans. “What worries me the most is: what does it do for the sustainability of public finances?” he said. He said spending cuts would be extremely difficult under the current circumstances. “The pressures on spending are huge and they’re only going to get bigger,” he said. “The next election, I suspect, will be more about public services than tax rates.” Liz Truss in her campaign office in London. Photo: Tayfun Salcı/Zuma/Rex/Shutterstock As well as its promises of tax cuts, the Trust promised to review the possibility of treating households as a single entity for tax purposes, to give incentives to stay-at-home parents and carers. Speaking during a visit to Little Miracles, one of a network of mostly self-funded centers caring for children with disabilities and life-limiting conditions, she said she would specifically review the taxation of families. “Working families are the foundation of a stable society and one of my top priorities as Prime Minister would be to ease the tax burden on families. They’re not just taking care of themselves, they’re building communities, charities and even businesses,” he said. Subscribe to First Edition, our free daily newsletter – every day at 7am. BST Labor MP Stella Creasy said: “Families across this country are crying out for affordable childcare so they don’t have to choose between their careers and their children. Instead of helping them and investing in supplies, Liz Truss seems to think that taxes should be used to make women stay at home. It shows you that this Tory party wants to take Britain back to the 1950s, not help everyone thrive in the 2020s.” In his interview with LBC, Sunak repeatedly emphasized his family’s relatively humble background and described himself as a “practicing Hindu”, saying he had returned to the temple his family still attends in Southampton recently.