FIANNA Fail leader Micheal Martin has been accused of "shafting" his constituency colleague and finance spokesman Michael McGrath after his secretary was added to the local election ticket behind Mr McGrath's back.
The row has erupted after Mr Martin's secretary, Mary Rose Desmond, was added to the ticket in the same area as Mr McGrath's brother, despite the fact she didn't contest the convention two months ago.
It comes as Mr Martin is facing mounting criticism of his "secret" National Constituencies Committee. The committee is accused of "cynically imposing" additional candidates in areas on his behalf – against the wishes of local organisations.
Because of the likelihood of controversy, names of members of this committee have been withheld from the membership of Fianna Fail.
Mr McGrath is known to be incensed after the party added Ms Desmond, who works in Mr Martin's constituency office in Turners Cross in Cork, as a fourth candidate in the 10-seat Carrigaline-Ballincollig electoral area. He declined to comment on the matter.
At the December convention, the party selected three candidates, including Mr McGrath's brother Seamus, who is a sitting councillor.
Seamus McGrath has reacted angrily to the move to add Ms Desmond to the ticket, branding it "deeply cynical".
He said the decision to add a new candidate without consultation was "a reminder of old-school politics, something we all thought and hoped was behind us."
Mr Martin has said there was always the likelihood that a fourth candidate would be added, because there are now 10 seats up for contention.
However, Mr McGrath disputed this. "It is a unilateral action by the hierarchy of the party with absolutely no consultation with the local party officers, members and public representatives," he said.
Mr Martin and Michael McGrath both represent the Cork South Central constituency, with Mr McGrath narrowly taking the last seat of five in the 2011 General Election.
Cork South Central will be a four-seat constituency at the next election, but Mr McGrath is unwilling to move from his home base of Carrigaline.
They are not close and have already endured a turbulent relationship.
Mr McGrath forced Mr Martin into having a free vote on the abortion legislation last year, having openly opposed his leader.
This is the second internal controversy surrounding candidates linked to Mr Martin.
His niece, Kate, was chosen for the city council ticket amid claims the South East ward was divided geographically to ensure her selection.
A spokesperson for Mr Martin said the party leader played no part in the selection of candidates.
His brother, Sean, a sitting city councillor, is also running to retain his seat.