The Labour Party is planning to move the writ for the Dublin South byelection in the Dáil next week.
Party leader Eamon Gilmore said the people of Dublin South have been under-represented in the Dáil for a combined period of some sixteen months as a result of the death of Seamus Brennan and the resignation of George Lee.
"This should not be acceptable in any democratic society. Nor should it be acceptable that the people of Donegal South West have been under-represented for more than a year or that, it seems, Fianna Fail intends to allow a similar situation to apply in regard to the vacancy in Waterford", Mr Gilmore said.
The Dublin South seat is one of three outstanding byelections to the Dáil also including Donegal South West and Waterford.
The results of an Irish Times poll, published last week, showed a majority of 60 per cent of voters wanted the byelections held now, with 24 per cent saying they should not be held at this stage.