Independent TD Marian Harkin will not be standing in next year's general election in the Sligo/ North Leitrim constituency.
Ms Harkin said yesterday that she would instead be concentrating on her career as an MEP for the North and West constituency.
However, she denied her decision to resign from the Dáil was in any way linked to a recent TNS mrbi-TG4 poll which suggested she risked losing her seat.
"I had that decision taken a long time ago," she said. "It's just that I didn't say it publicly. I wanted to keep the pressure up on the Government." She had effectively decided she would not seek an additional term when she was elected an MEP in June 2004.
"When I ran for Europe two and a half years ago, that's what I wanted to do and that's where I see my future," she said.
As an Independent, Ms Harkin felt she could operate "in a different way at European level". "It's different, no opposition, no government. My job is to amend legislation and I think I have an impact."
She said there was no member of her local constituency operation planning to run in her place.
The decision by Ms Harkin not to stand in the three-seat constituency is expected to leave Fianna Fáil and Fine Gael battling for the final place.
According to the recent TG4 poll, TDs John Perry from Fine Gael and Dr Jimmy Devins should be elected. Fine Gael is running two other candidates, Imelda Henry in Sligo and Michael Comiskey in North Leitrim, while Fianna Fáil is running Senator Eamon Scanlon alongside Dr Devins.
Meanwhile, Labour leader Pat Rabbitte announced last night that Arklow-based councillor Nicky Kelly is to be added to the party's ticket in Wicklow. He will be joining sitting TD and Labour deputy leader Liz McManus.
Mr Kelly missed out on a seat for the party in the 2002 general election, losing narrowly to Independent TD Mildred Fox.
The five-seat constituency is seen as a major target for gains by the Green Party, Fine Gael and Labour due to the retirement of two of the sitting TDs, Ms Fox and Fianna Fáil's Joe Jacob.
Mr Kelly was recently fined €730 at Wicklow District Court for motoring offences relating to a road traffic collision last year near Rathnew.
He picked up a mandatory five penalty points on his licence arising from his conviction for not having insurance. He was also convicted of careless driving and having no tax on the car.
In Co Meath last night, Fine Gael selected former Meath GAA football captain and All-Ireland winner Graham Geraghty to stand in the constituency of Meath West, alongside sitting TD Damien English, currently the youngest member of the Dáil.
The convention also selected Peter Higgins as the third candidate for the constituency to stand in the Trim area.
The Progressive Democrats also announced yesterday they will contest the five-seat Carlow-Kilkenny constituency where they have not held a Dáil seat since 1989.
Party leader and Tánaiste Michael McDowell yesterday announced the candidacy of Walter Lacey, a member of Carlow County Council and the party's only councillor in the twin-county constituency.
Mr McDowell said the party was "up for the challenge of winning a seat" and said that he was "currently looking at a number of people in Kilkenny" to find a running mate for Mr Lacey.