Whitbread has ended months of speculation by putting its conference and banqueting site the Brewery up for sale.
Based in London's Chiswell Street, the Brewery has been part of the Whitbread stable for more than 250 years and was the centre of the company's now defunct brewing operation until the end of the 1970s.
Christie & Co has been appointed to handle the sale, which is likely to raise £45m to £50m.
Christie director Jon Patrick described the site as a once in a 250-year opportunity.
It includes Brewers House, which already has planning consent for a 118-bedroom serviced apartment scheme, and the South Yard office block.
Whitbread group development director Desmond Taljaard said: "The sale of the Brewery is part of Whitbread's strategic intent to exit from non-core assets and focus on three core areas of business."
Company chief executive Alan Parker, who took up his role in June 2004, has focused on developing Premier Travel Inn, its pub and restaurant businesses and its David Lloyd Health Clubs.
In March Parker put Whitbread's franchised Marriott hotels into a joint operating company with franchisor Marriott International, which will sell them for around £1b within two years.
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