Former Minister Jim McDaid has resigned his Dáil seat.
The Donegal North East TD had been outside the Fianna Fáil parliamentary party for some time since he opposed the Government over the cervical cancer vaccine.
It means there will be another by-election for the Government to contend with, as there are now four vacancies in the Dáil.
The Donegal North East TD was at a health meeting last night, where he came in for some criticism and he apparently declared he had to come to a decision in a matter of hours.
Mr McDaid has often been surrounded in controversy - back in 2006 he announced he was retiring from politics, only to change his mind some months later.
This time however his resignation has been accepted by the clerk of the Dáil and it cannot be reversed.
The Government has said it doesn't necessarily rely on his vote - the reality however, is that on a couple of close calls his vote has mattered.