The Conservatives called on councils to utilise "usable" reserves of more than £2bn, with taxpayers in Wales facing an average bill increase of 7.3% per cent next year.

Laura Anne Jones warned council tax has “skyrocketed”, rising by 200 per cent or £1,400 over the past two decades while councils hold £2bn in so-called usable reserves.

She said: “Let me remind Labour that reserve funding is meant to be used for desperate times: those rainy days.

“Well, I would argue this is a rainy day, yet Labour is still hesitant to encourage councils to use reserves.

“It's completely immoral.”

Others accused the Tories of being disingenuous about usable reserves, which include individual school reserves, housing and capital funds, and grants for specific projects.