Rishi Sunak accused his Conservative leadership rival of “promising the earth to everybody” as he played down polling suggesting he is set to be defeated by Liz Truss.
The former British chancellor also fuelled speculation that he may decline to serve in any Truss administration if defeated, as he suggested that ministers need to agree with a prime minister on the “big things”.
It comes as the British foreign secretary, who is the frontrunner to replace Boris Johnson as British prime minister, was urged to be more transparent with her plans for an emergency budget to address the cost-of-living crisis.
Mr Sunak, in a wide-ranging interview on BBC Radio 2, insisted he is receiving a “warm reception” while campaigning even as he acknowledged that some Tory Party members are still angry at him for quitting Mr Johnson’s government.
Mr Sunak said: “If I actually spent all my time looking at the polls or reading newspapers, I probably wouldn’t get out of bed in the morning to do all these things.”
“There are a group of people among our members, and that is understandable, who are upset I resigned from government,” he admitted.
But he rejected suggestions that his campaign has not been “politically savvy” as he said he just wants to be “honest” with voters about the state of the British economy.
Ms Truss has said she would bring forward urgent plans to address rising energy bills if elected as prime minister.
But Conservative MP Mel Stride, who chairs the UK's Commons Treasury Committee, called into question reports that she is not planning to ask the independent Office for Budget Responsibility for a forecast ahead of the measures she is planning for next month.
Mr Stride, a Sunak supporter, told LBC: “At the moment the Liz camp are saying, I believe, that there will not be any OBR forecast produced at that time and that is kind of like flying blind.
“It means that you do all these dramatic things on tax et cetera, but you don’t actually know what the independent forecaster believes the impact will be on the public finances, and I think that is quite a serious situation were that to come about.”
Asked if OBR scrutiny would be bureaucratic in a time of crisis, Mr Stride said: “No. We are asking for transparency and reassurance that whatever whoever wins this contest comes forward with is affordable and not reckless.”
Mr Sunak’s attacks on his opponent’s tax-cutting plans come as the race to succeed Mr Johnson enters its final fortnight.
Mr Sunak's campaign had earlier called on Ms Truss to “come clean”, and claimed her plans to borrow in order to fund tax cuts are “dangerous”.
He told the BBC: “Liz’s plans are promising the earth to everybody. I don’t think you can have your cake and eat it. I don’t think life is that simple, and I think her plan risks making everything worse.”
Ms Truss has argued that tax cuts will help to grow the UK’s economy and boost prosperity.
A Truss campaign spokesman said: “The cost-of-living crisis means immediate action is required.
“A Truss government would seek to act as soon as possible to help people across the UK, by cutting taxes and introducing a temporary moratorium on energy levies.”
The OBR usually requires 10 weeks to carry out an analysis of the UK government's economic proposals, such as the budget or spring statement.
But an OBR spokesman said: “We would be prepared to publish a forecast for the new chancellor, should they request it.”
This could be carried out before the usual 10-week wait, as it did in October 2018 following Brexit negotiations and November 2020 during the pandemic.
Senior Tories have criticised the Foreign Secretary’s economic plans, with former minister Michael Gove accusing her in a Times article of taking a “holiday from reality”.
Yet the criticism has so far appeared to have done little to arrest the momentum of Ms Truss, amid reports and rumours speculating over who could make up her cabinet in the event of victory.
Mr Sunak, who according to reports might be offered the health portfolio, laughed off the suggestion when it was put to him during the BBC interview.
He also appeared to allude to concerns over the potential for cabinet clashes in such an administration.
“I am not focused on all of that and I doubt Liz is,” he said.
“I am not thinking about jobs for me or anyone else.
“One thing I have reflected on as well a bit is, being in a government, in cabinet, over the last couple of years, you really need to agree with the big things.
“Because it is tough, as I found, when you don’t. And I wouldn’t want to end up in a situation like that again.”
Both candidates have come under increasing pressure to deal with rising costs, and Ms Truss has signalled she could help firms and households with soaring energy bills with direct support this winter.
An energy company boss called on the Conservatives to end the leadership contest early to address rising bills.
Bill Bullen, chief executive of Utilita, told BBC Radio 4’s Today programme: “All through the summer, we’ve been hearing about customers in distress, customers who are worried that they’re not able to heat their homes over this coming winter.
“That’s why we’re saying to the government, you’ve got to take this decision to freeze prices at their current level right now.
“This cannot wait until September 5th or 6th. The Conservative Party needs to sort themselves out, decide who the leader is going to be this week, so that the Ofgem announcement on the 26th doesn’t have to happen.”
The UK's energy regulator Ofgem is set to announce the latest price cap on Friday, with predictions it could rise from £1,971 (€2,328) to around £3,600 (€4,252).
