Brewing giant Coors has announced it is to put the Cape Hill Brewery up for sale.
The sale of the Birmingham site (pictured) will mean the loss of up to 320 jobs and represents another major shake-up for the brewing industry.
The brewery was originally owned by Bass Brewers before passing to Interbrew when the Belgian brewer bought Bass' brewing interests two years ago.
It was subsequently sold on to Coors as part of a £1.2bn package that included the Carling lager brand, following intervention by the UK Government competition authorities.
The decision to sell the Cape Hill site was not wholly unexpected - Coors had refused to rule out any sell-off when in took on the site - but the Campaign for Real Ale (CAMRA) immediately attacked the decision, saying it would change the face of brewing forever.
Spokesman Mike Benner said: "I think this is a dangerous move for Coors. Before it has even found its feet in the complex UK brewing market, it is reducing its own capacity and weakening its production capability.
"This is the inevitable result of consolidation."
Coors defended the move, saying it had been a difficult decision to reach. "It is not an easy decision to propose closing a brewery and an announcement such as this is very sad, especially given the hard-working and loyal people we have at the brewery," spokesman Martin Thomas said.
"We shall be doing everything we can to support all employees affected by the announcement and consult with them fully over the coming months."
The company said brewing and packaging operations at the Cape Hill site would cease by the end of the year.
However, it added that up to 100 jobs would be created as production at its Burton site was increased and promised trade customers would not be affected by the sale.