Minister of State John Halligan has said he does not want to resign from Government but warned that promises made to him by Fine Gael negotiators over University Hospital Waterford have to be delivered.
The Independent Alliance TD told RTÉ News: "I really do not want to leave Government" but added "I will step down if I have to."
"I regret that it has come to this", he said, adding that he could not "sully" his principles.
Provision of a second catheterisation laboratory for UHW is at the centre of a dispute between the Government and Mr Halligan, a local Waterford TD and a junior minister at the Department of Jobs, Enterprise and Innovation.
Mr Halligan believes that a second cath lab is needed but this has not been recommended in a review, which was commissioned by Minister for Health Simon Harris in May.
Mr Halligan said he had supported the Government on many difficult issues, such as water charges, and this had resulted in "fire coming down on top of me."
He asserted that it was now up to Fine Gael to honour its side of their agreement regarding a new cath laboratory for UHW.
Meanwhile, fellow Independent Alliance Minister of State Sean Canney has said members of the group are going to meet as soon as they can to discuss remarks made by Mr Halligan to Sunday newspapers.