Boris Johnson has repeatedly refused to say whether his planned National Insurance increase will go ahead in April, as calls continue to mount for the tax rise to be postponed.
The Prime Minister insisted that new funds for the NHS had to be paid for but declined to guarantee that the 1.25 percentage point rise would still take place on time.
His reluctance to commit to the increase came just hours after a senior minister claimed that the entire Cabinet would back a delay to help ease the cost of living crisis.
The minister went on to suggest that the Prime Minister would also welcome a postponement, telling the Daily Mail that the decision was down to Rishi Sunak, the Chancellor.
“There would be no objection from the Prime Minister either because this is very much a Treasury policy,” they added.
“It is the wrong time to be raising taxes. We need to have a clear recovery from Covid before we start working out what we want to do about the fiscal balance. The ball is very firmly in the Chancellor's court.”
Echoing their concerns, David Davis, the former Brexit secretary, warned that Tory voters would "evaporate" unless the NI increase was scrapped.
The claim was dismissed by a number of senior government sources on Monday morning, with Nadhim Zahawi, the Education Secretary, insisting that raising NICs to pay for social care was “the right thing to do”.
But The Telegraph understands there are splits emerging in Cabinet.
Asked during a visit to a hospital in Milton Keynes whether he could guarantee that the planned hike would go ahead, Mr Johnson told reporters: “What we've got to do is look at all the ways we can address cost of living.”
Pressed a second time, he swerved the question, referring instead to inflation, supply chain problems and employment.
On the fourth time of asking, he signalled his desire to stick to the tax increase, stating: “Look at what we're investing in and look at what I think is the number one priority for people living in this country. The NHS has done an amazing job. But it has been under terrific strain.”
He added: “Listen to what I'm saying. We've got to put that money in, that investment in our NHS.”
However, he refused eight times to say whether the NICs rise would go ahead, instead repeating only that “ if you want to fund our fantastic NHS you have to pay for it.”
Speaking shortly after his interview, the Prime Minister’s spokesman adopted a firmer line, insisting the levy was critical to “tackling the massive” NHS backlog which had built up during the pandemic.
‘The right approach’
"It then seeks to address the long-standing problem of fixing our social care system, which unfairly penalises a small minority, and of course it also helps fund a pay rise for NHS staff which the public massively want to see.
"So this is the right approach to tackle this long-standing problem."
Asked about reports that the whole Cabinet would back a move to delay the rise, he said: "Cabinet took a collective decision to take this action, to put money into our NHS, to tackle the backlogs, to resolve the long-standing problem of social care and to fund a pay rise for nurses. The Cabinet stands behind that decision."
Speaking beforehand, Mr Zahawi, told BBC Radio 4's Today programme: "On the national insurance, the ￡36 billion is necessary because successive governments... of every colour have not dealt with this.
"It is really important to remember that the highest earners, the 14 per cent who earn the most, are paying 50 per cent - they are paying half of that contribution, and the lowest earners, 6.1 million of the lowest earners pay nothing, so it is as progressive as we can make it to deal with a problem that breaks many an individual in their old age.
"So it is really important to focus on why we are doing this, why I think it is the right thing to do, because it will finally create a system of adult social care that is sustainable and deliverable without breaking families."