Fine Gael tonight billed the defection of a Progressive Democrat councillor to its ranks as a symbolic blow to the government partners.
The decision of Progressive Democrats (PD) councillor Mary Mitchell O'Connor to switch allegiances was being seen as a further signal of the decline of the PDs.
Fine Gael leader Enda Kenny welcomed the move as a vote of confidence in his party.
"I'd like to formally welcome Mary Mitchell O'Connor to the Fine Gael ranks and wish her all the best as she joins our local government team on Dun Laoghaire County Council," he said.
"This decision by Cllr Mitchell O'Connor is a very positive vote of confidence in the Fine Gael Party and what we are trying to achieve.
"When deciding how best to represent her electorate, Cllr Mitchell O'Connor recognised the strength and focus of the Fine Gael team in her area and decided that she wanted to be a part of that team.
"This is the first move by a PD public representative to join an alternative party since the General Election and, I believe, reflects the reality that many of the existing PD public representatives are now facing."
Ms Mitchell O'Connor described the last election as a watershed for the PDs. "There has been an effective drift in terms of leadership and renewal. "A vacuum has been created at the top of the party where Mary Harney is effectively filling in at the minute that has yet to be filled.
"As a result I started to question whether the PDs were the best option for me to represent the electorate of Dun Laoghaire. "I consulted with my family and my supporters and decided that a re-energised and dynamic Fine Gael team under the leadership of Enda Kenny was the one I wanted to join," she said.
Ms Mitchell O'Connor was first elected to Dun Laoghaire/Rathdown County Council in 2004.
PA