Keir Starmer was accused of plotting to ditch the cap on council tax today during bad-tempered PMQs clashes.
The premier ducked as Tory leader Kemi Badenoch demanded to know whether the 5 per cent ceiling would be maintained.
Currently local authorities are obliged to hold a referendum for anything above the level.
But Ms Badenoch warned that the national insurance hike in the Budget would drive up costs for town halls on areas such as care services.
The Tories claimed there is a £2.4billion black hole in the finances for local government that would need to be filled with higher tax.
The party has calculated that would amount to a 6.6 per cent rise across the board, roughly £143 extra on a Band D property.
When Ms Badenoch asked directly whether the cap on council tax would be axed, Sir Keir replied: On the question of councils, she knows what the arrangements are.
Ms Badenoch said: I think the House would have heard that the Prime Minister could neither confirm nor deny whether the cap on council tax was being raised.
She added: With no separate funding for the Chancellors Budget announcements, care providers will likely see increased costs, which will cost councils more, and all of the £600(million) in grant increase he is giving will not cover what is required for adult social care.
It is clear that they had not thought through the impact of the Budget, and this is the problem with having a copy-and-paste Chancellor. Did they not realise care homes, GP surgeries, childrens nurseries, hospices and even charities have to pay employers national insurance?
Sir Keir insisted: We have put more money into local authorities than they did in 14 years – the absolutely catastrophic state.
We produced a Budget which does not increase tax on working people, nothing in the payslip, investing in our NHS, investing in our schools, so every child could go as far as their talent will take them, investing in the houses of the future.
If she is against those things, she should say so.