The redundant buildings, in Brewery Lane, form part of the plans by developers Centros for the regeneration of the canal corridor site. The £150 million scheme is currently under consideration by the Secretary of State, with a decision likely to be made in January.

However, Mitchell's this week gave the city council a Notice of Intended Demolition under Section 80 of the Building Act 1984 for the demolition of the buildings.

The proposed demolition does not require consent under current planning law, and under the Building Act the council cannot refuse such a notice, although limited conditions can be applied.

The legislation does not permit demolition to begin until the council has agreed conditions (to ensure proper treatment and sealing of services, and safety measures for demolition), or a period of six weeks has elapsed without response.

Green councillor John Whitelegg said he hoped to be able to block the move. An earlier attempt by the Bulk ward councillor for the buildings to be given a Building Protection Notice was rejected by the council.

"It would be an unmitigated disaster and a blow to Lancaster's aspirations to be regarded as an historic city and city with a precious heritage if these buildings were to be demolished," he said.

"The demolition would be an act of unrestrained vandalism and would result in the loss of a collection of buildings with enormous potential to enrich our cultural and regeneration efforts.

"I am very disappointed that we have done so little to protect these buildings, and now they are in danger of being swept away. It's vital that we stop this – the buildings are part of what makes Lancaster a distinctive and special place."

Mitchell's were unavailable for comment as the Guardian went
to press.