Sir Keir Starmer has defended the decision to axe winter fuel payments for millions of pensioners, as calls for a reversal of the policy continue.
A group of around 45 Labour MPs representing seats in northern England and the Midlands have joined those urging the government to rethink the move.
During Prime Minister's Questions, Conservative leader Kemi Badenoch pressed Sir Keir to "listen to his own party and change course".
The policy has partly been blamed for Labour's poor performance in last week's local elections in England, which saw the party lose two-thirds of the council seats it was defending.
Reform UK also defeated Labour in the Runcorn and Helsby by-election, overturning a majority of nearly 15,000 to take the seat by just six votes.
The results have led to growing calls to rethink winter fuel cuts from senior Labour figures, including Welsh First Minister Eluned Morgan.
But on Tuesday the government insisted it would not be changing the policy, which was introduced last year.
