LIZ Truss has not ruled out cuts to universal credit and other welfare benefits as she faces a growing backlash against the Conservative's budget.

In a BBC interview this morning as her party conference got underway in Birmingham, she was clear that pensions will rise in line with inflation, saying she has "committed to the triple lock" protecting them against price increases.

However, she refused to give the same guarantee for benefits and government departmental budgets.

Not ruling out rowing back on Boris Johnson's promise to raise benefit payments in line with inflation, she said: "This is something the Department of Work and Pensions Secretary (Chloe Smith) is looking at at the moment.

"She will make a determination on that and we will announce that this autumn."

The Prime Minister repeatedly refused to rule out cuts to public services, saying she would not pre-empt Chancellor's Kwasi Kwarteng's medium-term fiscal plan in November.

"What I'm going to do is make sure we get value for money for the taxpayer. But I'm very, very committed to making sure we've got excellent frontline public services," she said.

When it was put to her that some of her own MPs fear rising interest rates and more taxpayers' cash being eaten up will lead to spending cuts, she said: "I don't accept that argument and I will do what I can to win the hearts and minds of my colleagues across the Conservative Party because I believe we need to grow the size of the pie."

Ms Truss defended the dramatic break with past Conservative policy on stewardship of the public finances despite not having her own mandate at a general election.

She said people had voted for a "different future" in 2019, with hopes for investment in towns and cities, higher wages and economic growth.

"That is what our plan will deliver. I'm confident it will deliver. I'm absolutely confident that what we are doing on speeding up road projects, unleashing investment from the City, reducing taxes will deliver that," she said.

"I'm not saying it's not going to be difficult - we do face a very turbulent and stormy time - but it will deliver, it will deliver on the promises we made."

During the same interview the Prime Minister confirmed the abolition of the top 45p income tax rate for people earning more than £150,000 a year would do ahead.

Asked if she was absolutely committed to abolishing the 45p rate for the wealthiest people in the country, the Prime Minister replied: "Yes".

She added that the measure is part of a package to simplify the tax system and reduce tax.

"The 45p rate raises very little and makes our system more complicated," the Prime Minister said.

"We need to move away from the idea that everything is about how we redistribute resources.

"We also need to make sure we have a tax system that is competitive internationally and it is helping bring in investment and get people into work."

Former Cabinet minister Michael Gove was scathing about the plan, claiming the abolition of the 45p tax rate and lifting caps on bankers' bonuses at a time when people are facing hardship displays "the wrong values".

Pressed on whether he will vote for the package in the Commons, he said: "I don't believe it's right."

Another opinion poll illustrated the scale of the challenge facing Ms Truss to assert her authority over the party she only assumed leadership of in September.

The survey by Opinium put Labour on 46%, 19 points clear of the Conservatives on 27%. On the issue of the economy it found that a one-point lead for the Tories a week ago had become a 19-point advantage for Labour.

Writing in The Daily Telegraph, Labour leader Sir Keir Starmer said it is "unacceptable" that neither the country nor Parliament has had any say on the measures despite the chaos wreaked on the financial markets.

"The economy is not a laboratory experiment for the maddest scientists of the Conservative Party. Mortgages, pensions and family finances are not casino chips for a Government intoxicated by dogma," he said.

"There are many decent Conservative MPs who know this. My message to them is that Labour will work with anyone to ensure some semblance of economic sanity is restored."