ENGLISH Heritage says traditional cobbles should not be ripped up in Beverley.
But, despite the advice, East Riding Council is pressing ahead with removing stone setts from Saturday Market in January.
Conservationists have launched a petition and a website and are now planning a protest march on Saturday, December 22.
The authority says the £2.5m scheme is simply "maintenance" and it has already appointed contractors.
An English Heritage spokesman said: "We advised that it was better to keep the cobblestones rather than remove them completely and to only remove them where wheelchair access was needed.
"This advice was given before East Riding submitted their official plans. Since then, we have heard nothing from the council on their plans for the area.
"We believe it is possible to improve the market area and still keep the cobbles, which are important to the historic character of Beverley."
If the Saturday Market changes had been the subject of a planning application, English Heritage would have been a statutory consultee and its views would have been published in planning documents.
Instead, the work is being done from the maintenance budget and the council says public reaction to the plans for Saturday Market has been very positive.
That is not the view of conservationists who, backed by Beverley Civic Society, hope to have the works stopped.
Campaigner Richard Armstrong, of North Bar Without, said: "At a public meeting last week, there were 500 people and 99 per cent of them were against the plan."
Another campaigner, Adrian Stoke, of York Road, Beverley, said: "We intend to take the fight to the council. If there is a weight of support for the campaign, they would be silly not to sit up and take notice."
Nigel Leighton, director of environment and neighbourhood services at East Riding Council, said: "The works planned in Saturday Market are to address maintenance issues to the highways and footpaths.
"The local highway authority does not require planning permission by section 55 (2) of the Town and Country Planning Act 1990 as it is carrying out works on land within the highway boundaries, which are required for the maintenance or improvement of the road. The work does not involve development.
"Nevertheless, the council undertook a site visit with a representative from English Heritage in October and was advised to consider retaining the cobble setts or reuse them within the scheme."
The council has proposed to reuse some of setts in Old Waste, an area off Ladygate and at the ends of each row of parking spaces. It said English Heritage indicated that it was "not necessary" for it to be consulted again.
Mr Leighton said: "While some groups and individuals are in favour of retaining the cobble setts, the council has discussed the issue with other groups, including the disability advisory group, which feels the setts will cause problems for residents and visitors with disabilities.
"The council has made every effort to accommodate the feedback it has received on the scheme and has made a number of amendments, such as the incorporation of a channel parallel to the kerb to emphasise the curve in the road.
The council has also worked with the civic society to select the street furniture for the scheme, drawing on their knowledge and expertise.
"No matter how well laid, the setts will not provide a suitable surface for pedestrians and, in particular, less able-bodied people.
"Further consultation on Saturday Market is being undertaken regarding the phasing of the works, but no additional changes are proposed to the scheme design.
"The council will keep residents updated on the scheme."
