Sir Keir Starmer has refused to rule out further tax increases before the next general election.
This is despite a £40billion tax-raising Budget by Chancellor Rachel Reeves in October.
Asked by BBC Breakfast host Charlie Stayt about the possibility of further tax rises, Sir Keir said: “I don’t want to suggest we’re going to keep coming back for more because that isn’t the plan.
“What I can’t do is say to you there are no circumstances unforeseen in the future that wouldn’t lead to any change at all.
“If you look at Covid and Ukraine, everyone knows there are things we can’t see now, but I can tell you our intention was to do the tough stuff in that Budget, not keep coming back.”
The Prime Minister spoke to the BBC shortly after setting out six pledges, including a promise to put more money in the pockets of working people.
The PM and Ms Reeves have faced fury for raising National Insurance for employers and reducing inheritance tax relief for farmers in the Budget.
In the exchange, Stayt asked: “Can you say, in the clearest possible terms, whether from here on into the end of your term, there will be any tax rises? I’m talking about to business, National insurance or to people’s tax. Will there be any?”
Sir Keir said businesses had told him to “do the tough stuff” and ensure a “degree of certainty”, but that “things are not going to materially change”.