PD leader Ciaran Cannon was asked to leave a meeting of the party's national executive last Thursday evening as he had already formally notified the executive of his intention to resign from the party next week.

After the meeting started it is understood one of the national executive members made the point that he did not think it was appropriate for Cannon to remain at the meeting. This was because decisions had to be made at the meeting and the senator had already written to the national executive stating that he would be leaving the party on Tuesday next.

Sources insisted there was no rancour and Cannon apparently graciously accepted the potential difficulty. He stayed to give a report to the meeting about staffing issues but after that he excused himself and left.

The senator is expected to be revealed as a new member of Fine Gael later this week. It is expected that councillor Michael Maher, who took Cannon's seat on Galway County Council when the PD leader was appointed to the Seanad, will also join Fine Gael.

There is some irritation in the party that Cannon is leaving before the formal wind-up of the PDs, particularly as the process is almost complete. However, other sources were sympathetic, saying he was in a very difficult situation.

"Ciaran would like to have stayed until the party was formally wound up. He wanted to do the right thing. But [with the local elections approaching] he didn't want to leave Michael Maher in the lurch," one source said.

He added there was more irritation towards Fine Gael, which it is believed was pushing for Cannon and Maher to move immediately, than towards the party leader.

Cannon's resignation will result in Galway West TD Noel Grealish technically becoming leader of the PDs. As chairman of the parliamentary party, he automatically fills the leadership role and will oversee the final days of the party. This will be regarded with some irony by many in the party who blame the speculation over Grealish's future in the PDs, and the likelihood of him joining Fianna Fáil, for bringing matters to a head.

Cannon refused to comment when contacted by the Sunday Tribune and said anything that happens at a national executive meeting was private and confidential and he wished to respect that.

As first reported in the Sunday Tribune, the PDs continued to receive state funding after party members voted to begin the process of winding up the party. However, it is understood senior members of the party, including health minister Mary Harney, are keen for the PDs to return some of this money once the financial accounts have been completed and lodged with the Standards in Public Office commission.

The future of Harney and Senator Fiona O'Malley remain unclear. It is known that Taoiseach Brian Cowen wants Harney to rejoin Fianna Fáil and stay in the cabinet. O'Malley has been linked to several parties and is known to be well regarded by Cowen.