Dublin MEP Gay Mitchell has said he will not contest the European Parliament elections next year.
He said he believed that this was a good time to allow new candidates to emerge.
In a statement, he said: "When I first stood for the European Parliament in 2004 I did so at the request of the Party Leader, as Fine Gael only had three Dáil seats out of 43 in Dublin, one of which was mine.
“In 2009, Dublin was reduced from a four seater to a three seater and I stood again.
“Next year I will be 10 years in Parliament, and I have already served 26 years as a TD, having been first elected in my twenties.
“Fine Gael now has 16 TDs, three Senators and 36 councillors in Dublin.
“Taking all things into account I believe this is a good time to allow new candidates to emerge.”
In a statement, Taoiseach Enda Kenny thanked him for his many years of “dedicated service”.