Independent West Galway TD Noel Grealish has said he is withdrawing his support for the Government with immediate effect.
Speaking to RTÉ News, Mr Grealish said he would not vote to support the Government until such time as planned health budget cuts in the west are clarified.
When pressed if he would vote against the Government on every issue that came before the Dáil, Mr Grealish said there might be some issues that he would support on a personal basis, but the Government could no longer count on his support on every vote.
Mr Grealish told RTÉ News he was not trying to bring down the Government but was standing up for what he felt was right.
He said he wrote to Taoiseach Brian Cowen and Health Minister Mary Harney to inform them of his decision this morning.
The former Progressive Democrat TD said he had come to his decision following a briefing yesterday by the Health Service Executive on Budget cuts.
He said planned cuts of €19.5m for hospitals in Galway would have a 'huge impact on patient care'.
The Taoiseach said he looks forward to responding to Mr Grealish, but it has to be in the context of the budgets that are available.
Mr Cowen said there was a need for health services to stay within the levels and plans that were agreed at the beginning at the year.
He said it was in everyone's interests that the Government work within these plans.
Minister for Health Mary Harney said 'there is no deal and can be no deal' in response to the announcement.
Speaking at the opening of a €100m expansion at Blackrock Clinic in Dublin, Mary Harney said 'we don't have additional money to put into west of Ireland' adding that 'everyone has to live within their budgets'.
She added that patients will not be put in jeopardy and patient safety was her number one priority.
She said she is happy to meet Mr Grealish next week to provide the clarification he is looking for.