Half of the historic brewing home of Irish stout Guinness is to be sold and 250 brewing jobs axed under plans unveiled today by drinks giant Diageo.

But the group pledged to keep Dublin's famous St James's Gate brewing site open to protect the ``heritage'' of the Guinness brand and will spend part of a £520 million investment in renovating the brewery.

Diageo said it will instead close two smaller breweries at Kilkenny and Dundalk in Ireland, at the cost of more than half of the 450 brewing staff employed in the country.