Actor Tony Booth is backing a campaign to preserve a historic market in his local town centre.
The outspoken father-in-law of Prime Minister Tony Blair joined demonstrators outside Stalybridge's Victorian Market Hall in Greater Manchester.
Councillors in Tameside plan to lease part of the building to a major restaurant chain to help recoup some of the £1.5m they spent on refurbishing the landmark.
But protesters insist the deal will rob the town centre of a focal point.
Locals say the town needs market traders
Mr Booth, who lives in nearby Broadbottom village, has criticised council leader Roy Oldham for pursuing the change to the market hall.
He said: "Once again Roy Oldham and Tameside council appear intent on ripping the heart out of a community.
"So much money has been spent on the regeneration of Stalybridge in the hope of maintaining a sense of community.
"Why are Oldham and his cohorts now proposing to destroy an essential part of that community?
"Stalybridge market is at the heart and must remain at the heart of this community."
A group of about 150 people demonstrated outside the Victorian building on Wednesday lunchtime with placards saying 'Bridgeites ignored' and 'A market town without a market'.
Conservative councillor Colin Grantham agreed the move could damage the town.
But Mr Oldham replied: "The council has overseen in excess of £100m worth of investment in Stalybridge town centre.
"We're preparing to continue this work and make Stalybridge one of the leading towns of the north west. "
Mary Connelly, in her 80s, is among those who lament the passing of the municipal market.
She said: "My great-grandfather helped to build the hall in 1868.
"The tall market clock is our most famous landmark.
"The council promised us they'd refurbish the stalls to bring back the thriving trade."
Rick Malone, Stalybridge town centre manager, said of Tony Booth: "I'm surprised that somebody of his standing has lent his name to this protest without checking out the facts first."
Wednesday, 23 January, 2002, 18:00 GMT