The prime minister has told the BBC that his new government is “going to have to be unpopular” and make tough decisions in order to bring reforms.

Speaking on Sunday with Laura Kuenssberg in his first major interview in office, Keir Starmer said the only way to change the country was to do “difficult things now” even though “I know they are unpopular”.

Defending his decision to remove winter fuel payments from most pensioners, he said previous governments had “run away from difficult decisions” and Labour could only keep its promises if he acted in his first few months in office.

No 10 faces a potential rebellion in Parliament this week when there will be a vote on the decision to axe the payment for all but the poorest pensioners.

The prime minister said the decision was necessary because of the state of the country’s finances, accusing previous governments of avoiding confronting issues like the cost of winter fuel payments.

“I’m convinced that because they’ve run away from difficult decisions, we haven’t got the change we need for the country,” he said.

He said he was “absolutely convinced we will only deliver that change, I’m absolutely determined we will, if we do the difficult things now. I know they’re unpopular, I know they’re difficult, of course they’re tough choices.”

“Popular decisions aren’t tough, they are easy,” he added.

Sir Keir’s personal ratings have already suffered a drop since he took office, with the decision to axe winter fuel payments, repeated warnings about the state of the economy, and pressure on government spending ahead of the budget at the end of October.

The full interview with the prime minister where he responds to the Grenfell tragedy, the summer riots, and his upcoming visit to the White House will air at 09:00 BST on Sunday.

Sir Keir also spoke about the NHS in England, saying it had been been “broken” by successive Conservative-led governments – and the state it is now in is “unforgiveable”.

He said a review of the health service to be published on Thursday finds changes to the NHS were “hopelessly misconceived”.

Sir Keir added that the review by an eminent surgeon, Lord Darzi, is expected to reveal too many children “are being let down” by the health service.

In response to Sir Keir’s comments, shadow health secretary Victoria Atkins said after 14 years in opposition, “Labour’s instinct is to politicise children’s health, rather than provide solutions and reform our NHS”.

Watch the full interview from 09:00 BST on Sunday on BBC One or BBC iPlayer.