The Conservatives have slammed proposals by local authorities to apply a new levy on supermarket parking spaces under the Sustainable Communities Act.

The attack came after the Local Government Association published plans by a number of city and district councils, such as Exeter and Lewes in East Sussex, to levy business rates on supermarket car parking spaces in order to support local sourcing and discourage car use. The proposals include a scheme to reduce the levy for stores that source a certain percentage of goods from the local area.

Retailers' free car parks are currently not separately rated for business rates, although the general premises are. Conservatives estimate that the new levy could cost supermarkets more than £580 per space per year.

Shadow Secretary of State for Communities & Local Governemnt Caroline Spelman said: "Parking charges have soared in the last decade thanks to explicit Whitehall guidance telling town halls to levy higher fees. Now I fear struggling families will be punished with new taxes as they do their weekly supermarket shop.

“This is just another Labour excuse to impose higher taxes and fill Gordon Brown’s black hole in the public finances. Ministers are off their trolley if they think there will be any public support for these plans, and Conservatives will oppose such taxes every step of the way.”