Chancellor Kwasi Kwarteng has insisted he is "not going anywhere", despite the market turbulence he admitted was caused in part by his policies.
Asked if he and PM Liz Truss would still be in their jobs this time next month, he said: "Absolutely, 100%."
Mr Kwarteng also sidestepped questions about whether he would U-turn on parts of his mini-budget, saying: "Our position hasn't changed."
He is facing growing calls from Tory MPs to rethink his tax-cutting package.
Discussions are under way between the prime minister and backbenchers about what her party can accept.
The mood among Tory MPs is angry and fatalistic. "It's checkmate, we're screwed," one told the BBC.
"There is no question in my mind, they'll have to junk loads of this stuff and U-turn," another said.
Some think the government's tax-cutting plans should be reversed, while others think the help with energy bills should be more targeted.
Other scenarios being discussed by Tory MPs include the chancellor resigning or the prime minister being ousted.
However, there is little agreement on what should happen next or who should replace Ms Truss if she is removed.
The government has already U-turned on its plan to scrap the top rate of income tax, but this only made up £2bn of the tax cuts announced by the chancellor last month.
He is under pressure to spell out how the remaining £43bn will be paid for, and how he will get the UK's national debt falling.
Mr Kwarteng is due to deliver a statement on 31 October, along with independent economic forecasts.
Pressed on whether there could be further U-turns on his mini-budget, Mr Kwarteng, who is in Washington for an IMF meeting, said there would be more detail on 31 October.
Asked about the possibility corporation tax could rise, Mr Kwarteng said he was "totally focused" on delivering his mini-budget.
Ms Truss has pledged to scrap a planned rise to the tax, which was set to increase from 19% to 25% in 2023.
On Wednesday, she said it would be "wrong" to raise corporation tax "when we are trying to attract investment into our country at a time of global economic slowdown".
In an interview with Sky News, former Home Secretary Priti Patel said the market would now "dictate" the prime minister's decision on corporation tax "primarily because we want to see stability".
The pound rose against the dollar as rumours emerged about a possible government U-turn.
However, it later fell back after stronger-than-expected inflation data from the US drove up the value of the dollar.
In an interview in the Daily Telegraph, when asked about the market response to the speculation of a U-turn on corporation tax, Mr Kwarteng said: "Let's see."
However, he added that he still thought ensuring "competitive" tax rates for businesses was a "great idea".
The chancellor's mini-budget on 23 September has caused turmoil in the financial markets and prompted the Bank of England to intervene to protect pension funds.
Mr Kwarteng acknowledged there was "some turbulence" after his mini-budget but said there was "a very dicey situation globally", with inflation, potential interest rate rises and energy price spikes affecting everybody.
Watch: I am not going anywhere - Kwasi Kwarteng