Dublin City Council Green Party member Bronwen Maher has resigned from the party.
Ms Maher said she made the decision due to irreconcilable differences regarding policy and the direction of the party leadership.
She said she could not support the party leadership as a result of its deliberate change of policy direction.
She said the party has sacrificed its role as a watchdog for a weak, ambitious programme for Government.
In a letter to the Party Leader John Gormley, Ms Maher said the party is now seen as propping up Government. She accused the Green Party of having no top or bottom line and she said its role in Government is ill-defined.
Ms Maher said she would concentrate on getting herself re-elected in the Clontarf electoral area. She confirmed this morning she did not speak to Mr Gormley since sometime after Christmas when he rang her for a favour.
She also said she had not made the decision to leave the Greens to improve her chances of re-election to the City Council.
Greens 'have no Govt strategy'
She said being re-elected would be equally as difficult be she in the party or out. The councillor added that she wants to be part of a party that has a more social justice focus, for now she remains as an independent.
She accused the party of having no strategy in Government.
In her open letter to Mr Gormley, Ms Maher said the Green Party had stood for activists protesting against the Poolbeg Incinerator, the M3 and Tara, the Shannon stop-over and the Corrib gas project.
She said the party has traded that role for a weak policy platform, whilst at the same time supporting cuts in health and education, public transport and equality cuts.
She said the withdrawal of a life saving vaccination programme recently is also a major issue for her.
The gathering economic gloom is thought to be adding to disillusion among some in the Green Party at their performance in Government.
But after the resignation of Cork City Councillor Chris O'Leary yesterday, the party leadership insisted it is in Government for the long haul.
Green Party senator Deirdre de Búrca says she was is not surprised by the resignation of Cllr Maher.
She said that Cllr Maher was never happy that the Green Party went into Government with Fianna Fáil.
Senator de Búrca said Mr O'Leary and Ms Maher are more than likely considering their chances in the upcoming local elections.
Ms De Búrca said she hoped their resignations will be the last from the party.