Liz Truss must recall Parliament in response to the chaos in the financial markets, Keir Starmer has demanded.
“The government has clearly lost control of the economy,” the Labour leader said.
“What the government needs to do now is recall parliament and abandon this budget before any more damage is done.”
It comes after the Bank of England was forced to take emergency action on Wednesday – less than a week after the Chancellor delivered his mini-Budget with billions of pounds worth of tax cuts.
In a statement in response to market turmoil, the BoE said it would buy up long-term government bonds because of the “material risk to UK financial stability”.
The Labour leader said the move by the Bank of England “is very serious”.
He told Sky News: “And I think many people will now be extremely worried about their mortgage, about prices going up, and now about their pensions.
“The government has clearly lost control of the economy but unlike other situations where it may be a world event, an unexpected event that causes this sort of crisis, this is self inflicted.
“This was made in Downing Street last Friday.
“And for what? For uncosted tax breaks for those earning hundreds of thousands of pounds.”
In extraordinary comments on Tuesday evening the International Monetary Fund also urged Mr Kwarteng to change course in an extraordinary statement.
The organisation said the government should “re-evaluate” its tax measures – “especially those that benefit high income earners”.
The Tory MP Robert Largan also said he had “serious reservations” about the chancellor’s announcements last week, saying cutting the 45% tax rate for those earning over £150,000 “is a mistake”.
Before Mr Starmer’s comments Shadow Chancellor Rachel Reeves also called on the Mr Kwarteng to make an urgent statement “on how he is going to fix the crisis that he has made”.
She said:”People will be deeply worried about the impact of this turmoil on their mortgage, their pensions, and their cost of living.
“This is a crisis made in No 10 and is the direct result of the Tory government’s reckless actions, which include tax cuts for the richest 1%.
“Their decisions will cause higher inflation and higher interest rates – and are not a credible plan for growth.”
Their remarks came after the Liberal Democrat leader Ed Davey said the PM has 24 hours “to fix this economic disaster and prevent people losing their homes”.
He added: “Now is the time for the Prime Minister to recall Parliament to reassure not just the financial markets, but also British homeowners at risk of higher mortgage costs.
“Truss and Kwarteng must come forward and spell out how they will repair the damage from their shambolic budget.”
Scotland’s First Minister Nicola Sturgeon also echoed the call, saying the UK is in the “grip of (a) rapidly deterorating economic crisis”.
As it stands, MPs are not due to return to Westminster until October 11 following the party conference recess.