Nigel Farage gave a press conference on Tuesday, highlighting £25bn of savings he claims Rachel Reeves can make in her budget - including slashing overseas aid and welfare for foreign citizens.
But he said the areas where the local councils are now run by Reform are experiencing "massive problems" with their finances and may have to raise council tax.
The Reform leader claimed that when campaigning in the local elections in May, he "did not make a single promise - not a single promise in that election campaign that we'd be able to freeze or cut council tax".
"I never said it once. And you know why? Because I realised the massive debts that we were inheriting from those county councils."
Read more: What taxes could go up now?
A turquoise tide saw Reform gain control of 10 councils and win some 600 local councillors.
Farage promised a "DOGE" unit, inspired by Elon Musk's initiative in the US, to slash waste.
But most councils have indicated they will have to raise council tax, as they grapple with budget shortfalls and the pressures of adult social care.
I asked him why voters should believe he could easily find spending to slash in national government, if the record in local councils was anything to go by.
Mr Farage said: "There is a massive problem and this is going to need the national government to work with the local government to reduce those burdens.
"Are we determined to make changes? Yes. Will we cut debt? Yes. But can we give people a free ticket at this moment in time on council tax? No."
Kent County Council - where a leaked phone call exposing tensions about budgets led to councillors being suspended - is expected to raise council tax by the maximum of 4.99% next year.
Durham County Council is reported to be looking at raising parking charges.
Farage added later in the press conference that he hoped councils would keep their rises to the level of inflation, 3.8% in September.
(c) Sky News 2025: No 'free tickets' on council tax under Reform
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