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.