A bid by Bee Gees fans to save a former cinema building where the brothers first performed has been rejected by its owners, campaigners claim.
The Stayin' Alive campaign said the Co-op was selling the Manchester site to a private retirement flats developer.
But a Co-op spokesman said no final decision had been made about its future and "discussions are ongoing".
The Gaumont cinema in Chorlton was where the Gibb brothers made their live debut as The Rattlesnakes in 1957.
The Chorlton Community Land Trust, which raised more than £300,000 to save the site and is behind the Stayin' Alive campaign, wanted to turn the building into a community resource and put forward a £2.2m bid with a commercial developer.
Steve Goslyn, Chorlton Community Land Trust chair, said it was "with great disappointment" that it learned that Co-op Funeralcare had opted to sell the site which is currently a funeral home.
He added: "Sadly, the Co-op has decided to allow the building to be demolished and have thwarted local residents who were ready to invest in making our community a better place for us to live."
Campaigners hoped the venue could include a new GP practice alongside a gym and affordable housing.
The Gibb brothers - Barry, Robin and Maurice - were born on the Isle of Man but later moved to Keppel Road, Chorlton, where the family lived for seven years.
Mr Goslyn said campaigners were meeting at the end of the month to decide whether to fight the plan or make a further attempt to lobby the Co-op.
Co-op Funeralcare spokesman said at its last meeting with the trust the business expressed a number of concerns in relation to the proposal.
"Contrary to their comments, however, we have not yet reached a final decision in relation to the site and we are continuing to look at options which ensure the heritage of the site and its ultimate end use, benefit the local community.
"We have not entered into any contract with a preferred bidder and discussions around the future of the site are ongoing."