Brewer Scottish & Newcastle has announced plans to close its Reading brewery with the potential loss of 362 jobs.
The Foster's and Newcastle Brown Ale maker, which is being bought by European rivals Heineken and Carlsberg for £7.8 billion, said the site would close by early 2010.
S&N said closure of the former Courage brewery - open since 1979 - was the "most viable option going forward".
The closure follows the company's November decision to shut a bottling plant at the Reading site, costing around 250 jobs. S&N has also shut breweries at Newcastle and Fountainbridge in Edinburgh during recent years to cut costs.
S&N said the latest move would address a "general over-capacity" in the UK brewing sector - as well as saving the brewer around £13 million a year.
The company's group operations director, Stephen Glancey, said: "The nature of the Reading site, the amount of investment required to make it competitive and its relative cost compared to other UK facilities means that there is a strong business case for closure."
The closure of the 58-acre site will leave S&N with around 3,000 UK staff. It will begin talks with union officials in the next few days.
The company added: "S&N will work closely with local agencies to ensure that the impact on the local economy and community is minimised."
The Edinburgh-based group - the UK's last major independent brewer - has informed its prospective new owners of the plans.
The Unite union said it was "outraged" by the announcement, adding that workers were still "reeling" from the effects of cuts announced by the company last year.
