The Fianna Fail negotiator in the talks on forming a government has conceded that his party will have to support a minority Fine Gael-led coalition, if Micheal Martin loses Wednesday's vote for Taoiseach.
Dublin Bay South TD Jim O'Callaghan yesterday said it was "highly unlikely" that the party would be able to form a minority government without any votes from Independents.
He said the party would need to be "realistic", given that Fine Gael has 51 votes, including the support of Tipperary TD Michael Lowry.
"If we don't secure any votes from the Independents on Wednesday, we will see that it's going to be highly unlikely for Fianna Fail to be able to form a minority government," Mr O'Callaghan told RTE's This Week programme.
Fianna Fail has privately conceded that the party will lose Wednesday's vote for Taoiseach.
But senior party figures have now ruled out seeking the removal of acting Taoiseach Enda Kenny, with one source last night describing him as "Fianna Fail's greatest asset".
Mr Martin was boosted by a Sunday Independent/Millward Brown opinion poll which shows more than twice as many voters prefer him to Mr Kenny as candidate for Taoiseach.
In contrast, there is now renewed concern within Fine Gael over Mr Kenny's lack of popularity with the electorate.
The Fine Gael leader has scheduled talks with the Independent Alliance tomorrow before a round-table discussion with all 15 Independents at 6pm.
Fianna Fail is holding separate talks and has drafted in Galway West TD Eamon O Cuiv to answer questions on the party's proposals on agriculture and rural affairs.
The two party leaders are now due to meet on Thursday.
Meanwhile, the renewed focus on Mr Kenny's leadership is a cause for concern, according to Fine Gael sources.
"Any focus on Enda Kenny's popularity is not good for us, particularly as this process enters a critical phase," the source told the Herald.