Marc MacSharry has confirmed he is leaving Fianna Fáíl as he accused the party of “creating new rules on the hoof” to keep him out.
The party is currently investigating a complaint made against the Sligo-Leitrim TD by councillor Donal Gilroy.
It was expected that Mr MacSharry, who quit the party in September 2021 ahead of a vote of no confidence in Foreign Affairs Minister Simon Coveney, would be readmitted to the party two weeks ago.