After markets reacted negatively to his package of tax cuts, the Chancellor will set out his plan to get UK debt falling earlier than planned.
He will reveal how the cuts will be paid for later this month, despite previously saying he wouldn't.
The 45p rate of income tax was scrapped for higher-earning people.
Mr Kwarteng wanted to move forward without distraction.
The prime minister said that abolishing the top rate of tax was only a small part of the plan.
Mr Kwarteng acknowledged the "turbulence" caused by his mini-budget, which saw the pound's value plummet and the Bank of England bail out pension funds.
He promised to deliver the rest of his tax cuts even though he didn't have a majority in the Commons.
Ms Truss wrote in The Daily Telegraph that her government had a "firm commitment to fiscal responsibility".
She wrote that she and the chancellor had a clear plan for economic success and security.
The medium-term fiscal plan, which will outline how the government plans to cut the UK's debt, won't be ready at the end of November according to the chancellor.
The debt plan was expected this month and will be announced on Tuesday, according to a source.
Chris Philp, the chief secretary to the Treasury, said on Monday that the plan would be set out on November 23.
The chancellor was under increasing pressure to release the plan earlier in order to shore up market confidence.
The chancellor has been willing to do what it takes to regain confidence since the mini-budget, according to the economics editor of the British Broadcasting Corporation.
The Office for Budget Responsibility was asked by the chancellor to report back to him by the end of the month after the mini-budget.
The OBR gives an indication of the nation's finances. The government was given a draft forecast before it announced its package of tax cuts.
Mr Kwarteng and Ms Truss held emergency talks with the chairman of the OBR.
She said that the budget watchdog's assessment was not yet ready.
There is no need to publish something that is not ready. That would cause a lot of confusion.
The Conservative Party's dramatic slide in the polls has caused the government to change its mind about the mini-Budget.
The OBR will analyse the tax-cutting agenda of Ms Truss to see if it can deliver the economic growth it has promised.
It is not a U-turn on the scale of the 45p tax rate.
The statement has been brought forward by the Treasury.
The prime minister and the chancellor have allowed the impression that the statement wouldn't move from there.
Chris Philp, the chief secretary to the Treasury, didn't seem to know that the date was changing, even after the chancellor mentioned a change in his speech.
New numbers for borrowing will be provided by the OBR.
There will be forecasts for economic growth.
The chairman of the Treasury Committee said he had pressed the chancellor very hard and that he had listened to.
Bringing the OBR forecast forward should calm markets more quickly and reduce the upward pressure on interest rates to the benefit of millions of people up and down the country.
The chancellor's refusal to release the OBR's forecast was misguided and harmful.
She said that the government's continued failure to publish the forecast suggests that they have something to hide.