Prime Minister Andy Burnham has warned that the NHS "will collapse" unless England's social care system is reformed, telling the BBC he could not commit to building a new system before the next election but would not want to leave office without delivering "substantial change".

Speaking to the BBC's Laura Kuenssberg on Sunday in his first major broadcast interview since entering Downing Street, Burnham said the health service would never return to "good waiting time standards until we fix social care". The intervention marks the clearest signal yet of the domestic priorities of a prime minister who took office only a week ago, on 20 July 2026, following the resignation of Sir Keir Starmer.

"If we don't do it, the NHS will collapse under the weight of trying to care for people who've really not really needed to end up in the NHS system," Burnham said. He added: "I will go as quickly as I can on the reform of social care. I think there are major changes you can make before the next election. This costs the NHS billions of pounds, and we will never get the NHS back to good waiting time standards until we fix social care."

The warning matters because social care reform has defeated successive governments for more than a decade, and because the pressure it places on hospitals — through delayed discharges and avoidable admissions — is widely regarded as a central drag on NHS performance. Burnham, a former health secretary, is staking early political authority on an issue that has proved politically toxic in the past.

Despite the urgency of his language, the prime minister declined to set a firm timetable. "Whatever political capital I have, I will put in to fixing broken social care, and I would not want to leave office without having brought in the substantial change, the new system of social care that you describe," he said. "I can't put a timeline on it right here, right now." The next general election is not expected for around three years.

Burnham is due to set out his thinking on adult social care in a speech on Wednesday. He is not expected to unveil a fully formed system. Instead, according to the BBC, he will announce that he is accelerating the timetable for the Casey Commission, the independent review into long-term care funding chaired by Baroness Louise Casey. Her final recommendations had not been expected until 2028, but the prime minister wants that work completed this year.

Unlike NHS treatment, social care in England is not free at the point of use. In England and Northern Ireland, anyone with savings above £23,250 is not entitled to help with care costs from their local council, though the rules differ in Scotland and Wales. Reform options under discussion range from making care free at the point of need to capping the amount individuals must pay.

Sarah Woolnough, chief executive of the King's Fund, told BBC Radio 4's Today programme that the current arrangement was a "punitive system" under which many people go without the care they need, with one in seven paying more than £100,000 towards their own care. She noted that a universal, NHS-style model — an idea Burnham has long favoured — "would be expensive, but on the scale of what we spend on other public services — around £200bn on the NHS — we are talking for some of these options of low billions per year".

Woolnough also cautioned against framing reform purely as a way to relieve hospitals. "Social care is about far more than relieving pressure on the NHS or reducing delayed discharges," she said. "At its heart, it is about helping people live independently and with dignity. If the Prime Minister wants to succeed where previous governments have failed, he must make a positive case for reform and build a shared understanding of why change matters."

The question of how to pay for reform has already opened a dividing line with the opposition. Conservative leader Kemi Badenoch has written to the prime minister urging him to rule out tax rises or increased borrowing to fund any overhaul, arguing that reform must be fair to those who have already saved for their own care. Burnham has not specified a funding mechanism.

The issue carries personal history for the prime minister. As health secretary under Gordon Brown in 2009, he first floated the idea of a universal social care system and later pursued a compulsory levy to pay for it — an option that included letting people defer payment until after death, which the Conservatives branded a "death tax". More recently, Sir Keir Starmer faced criticism after Labour dropped a planned £86,000 lifetime cap on care costs in England around two years ago.

In the same interview, Burnham signalled a tougher line on welfare, suggesting it should be made harder to claim benefits and saying the country had to be "really serious" about reducing the welfare bill. He ruled out an early general election.

On foreign affairs, the prime minister said he had enjoyed a "good first exchange" with US President Donald Trump, whom he described as "really warm", but added that he would be prepared to call Trump out "to defend Britain's national interest before anything else" if he judged it necessary.

Burnham became prime minister through an unusually rapid change of government without a general election. Starmer announced on 22 June that he intended to resign as Labour leader and prime minister, citing a lack of confidence among his MPs. Burnham, who was nominated by more than 94% of Labour MPs, was the only eligible candidate when nominations closed and was acclaimed as party leader on 17 July, taking office three days later. A former MP of 16 years who served in Cabinet under Tony Blair and Gordon Brown, he left Parliament to become mayor of Greater Manchester before returning to front-line politics.

Since taking office he has reshaped the Cabinet, appointing Yvette Cooper as health secretary, moving Ed Miliband to foreign secretary and John Healey to the Treasury, while retaining Shabana Mahmood as home secretary. Burnham has also indicated he intends to work each week from a new departmental base in Manchester, dubbed "Number 10 North", a move he has cast as anchoring power beyond London.

The detail of Wednesday's speech, and whether the acceleration of the Casey Commission is formally confirmed, is expected to shape the first substantive test of the new government's domestic agenda.