A demonstration will rally outside the city's Guildhall tonight by objectors fighting city council plans to build a £9.1 million multi-storey car park.

It is being organised by the Canterbury Clean Air campaign group which says the proposed development in Station Road West will add to air pollution in an area already failing to meet environmental targets.

The group is already locked in a legal battle with the authority over the Local Plan which it says fails to address the problem.

The principle of the new car park - which will increase the capacity of the existing facility from 129 to 374 spaces - has already been approved by the council.

But tonight it has to get the approval of the authority's planning committee, which is said to be non political.

Placard carrying objectors are expected to gather outside the Guildhall from 5.45pm to make their point as councillors and members of the public arrive for the start of the meeting at 6.30pm.

The council argues that the extra parking capacity is needed to meet the growing demand of the high speed rail link.

It claims that due to the provision of 40 electric car charging pays and the growing use of the vehicle, it will have a "negligible effect" on air pollution in the future.

But that claim, along with the huge cost and appearance of the planned building, has prompted hundreds of objections and an e-petition on the council's website.