Two of the biggest unions in the country have heaped further pressure on Sir Keir Starmer's government over its decision to cut winter fuel payments for more than 10 million pensioners.
Sir Keir has said the cut - which will mean some pensioners lose out on £200 to £300 a year - was necessary due to the state of the country's finances.
The Prime Minister could face a rebellion at a vote in the Commons tomorrow (Tuesday), should some Labour MPs refuse to support the policy.
A number of MPs and charities have already raised concerns about the impacts of the cut, but now both Unite and the Public and Commercial Services (PCS) Union have criticised the plan.
Sharon Graham, Unite general secretary, told the BBC the government need to be "big and brave enough" to admit to their mistake, while she also criticised the government for "leaving the very rich and wealthy untouched".
"They've got to make different choices. And of course, people may vote with their feet at the next election," Ms Graham added.
"Labour get one shot to get this right.''
She also called for the introduction of a wealth tax, while speaking at the TUC's annual conference in Brighton.
Meanwhile, Fran Heathcote, the general secretary of the PCS union, said: "I can see a situation where, if they continue along the line that they're, they're heading with, with not just winter fuel payments but with social security and benefits more generally, there will be a real backlash and that could take the form of industrial action... because lots of unions represent low paid workers."
Sir Keir told BBC's Laura Kuenssberg he was "going to have to be unpopular".
He added: "When we talk about tough decisions, I’m talking about... the things the last government ran away from."