Fianna Fáil have confirmed Bertie Ahern has resigned from the party in a letter received this morning.
The former Taoiseach announced his resignation at the weekend ahead of a motion to expel him to be taken next Friday night.
Another letter of resignation from Councillor John Hannon has also been received.
A meeting of the National Executive of Fianna Fáil will go ahead next Friday anyway to discuss the re-organisation of the Dublin Central constituency.
Although no finding of corruption was made against Mr Ahern, Judge Alan Mahon said he did not believe the then Taoiseach's evidence on his financial affairs and payments of more than a quarter of a million pounds into accounts linked to him between 1993 and 1995.
Mr Flynn, who served as a European Commissioner, was found to have secured a donation for Fianna Fáil only to keep it for himself and the money was used to buy a farm.
Former ministers Ray Burke and the late Liam Lawlor were also fiercely criticised for their behaviour.
Others in Fianna Fáil singled out by the tribunal and facing expulsion at the Friday meeting are councillors GV Wright, Don Lydon and Finbar Hanrahan.
In an article in the Irish Times today, Mr Ahern described his resignation as a real emotional wrench and warned that he will vindicate his good name.
The three-times Taoiseach reiterated that he has never taken a corrupt payment and that he told the truth at the tribunal, which has left him deeply wounded.
There has been no indication from the Flynn family in Mayo of the former commissioner’s intentions.
Meanwhile, the disciplinary committee of Fine Gael will meet this week to deal with findings against members including Olivia Mitchell TD, who took IR£500 from corrupt lobbyist and former government press secretary Frank Dunlop while holding a council seat.
Another Fine Gael member, Anne Devitt, a sitting councillor, was found to have behaved inappropriately over the Cargobridge lands.