Labour Party TD Brian O'Shea has become the latest deputy to announce he will not contest the forthcoming election.
Mr O'Shea has represented Waterford since 1989.
In a statement this morning, he said he had arrived at this 'very difficult' decision following long reflection and discussions with his family over Christmas.
He said that the time had come for him to move on, and that given Labour's increased support, it was an appropriate time to introduce new candidates that will be elected.
Elsewhere, Fianna Fáil TD and Minister of State Jimmy Devins has also said he will not be standing in the election.
Taoiseach Brian Cowen described the Sligo TD as an 'able, affable and intelligent politician'.
FF ministers to contest Dún Laoghaire seat
Ministers Mary Hanafin and Barry Andrews have been selected to contest Dún Laoghaire for Fianna Fáil in the General Election.
There had been suggestions that one of the two might move to the neighbouring Dublin South constituency, which will not have a sitting Fianna Fáil TD as a candidate.
Dún Laoghaire has lost a seat due to boundary revisions and will now be a four-seat constituency.
The other TDs in the constituency are Green Party Minister of State Ciarán Cuffe, Labour leader Eamon Gilmore and Fine Gael’s Sean Barrett.
Two current Fianna Fáil TDs will also contest the Dublin South West constituency - Conor Lenihan and Charlie O'Connor.
Minister for European Affairs Dick Roche and Arklow-based councillor Pat Fitzgerald have been selected to run for Fianna Fáil in Wicklow.