Diageo's 650 million (250m) investment in a new Irish brewing centre will be the company's largest in its ten-year history but will be accompanied by closures and redundancies elsewhere in the business.
Paul Walsh, Diageo chief executive, said the state-of-the-art brewery near Dublin represented "the single biggest capital investment made by Diageo in its supply infrastructure since the company's creation ten years ago".
The drinks company's development proposal would also include the rejuvenation of its long standing St. James' Gate brewery.
"[This investment] will enhance the cost competitiveness of our global beer operations," Walsh added.
However Diageo's plans for expansion do not come without casualties as the breweries in Kilkenny and Dundalk will be closed on completion of the new larger facility in 2013.
Walsh said the company recognised the "impact this proposal would have on employment levels".
He added: "I also want to fully acknowledge the huge role and heritage of the Kilkenny and Dundalk breweries, which would cease operations once the new brewery is fully commissioned.
"I believe that the lessons and experience we draw from their valuable tradition and heritage can only help to enrich our new brewery."
There will be a net reduction of approximately 250 employees when the new breweries are operational from 2013 onwards, the company said.