The Munster MEP, Pat Cox, told the European Parliament in Strasbourg today that he will not be standing as a candidate in the forthcoming European elections in June.
Mr Cox said that he had, with mixed emotions, told his Munster constituency staff this morning that he would not be a candidate on 11 June.
Mr Cox's remarks came at the end of his final address as President of the European Parliament.
Mr Cox said that his 15 years as an MEP, including a seven-year term as President and vice president of the Liberal Group, had been the greatest experience of his life.
Mr Cox's decision not to run will fuel speculation that he may secure, or is hoping to secure, the post of Ireland's next EU Commissioner.
The parliament gave Mr Cox a standing ovation, and there were warm tributes for his tenure as president from the group leaders.