Fine Gael ministers are now seriously concerned that the Government will not be able to pass the Budget in October after a week of controversy over the EU Commission's €13bn tax judgment against US tech firm Apple.
Fine Gael Cabinet ministers are incensed with the Independent Alliance ministers, Shane Ross and Finian McGrath, and are now openly talking about the prospect of bringing down the Government.
Despite eventually reaching a deal on the Apple State aid controversy, there is still bad blood between Fine Gael and the Alliance over the embarrassing stand-off that made international headlines.
Last night, Fine Gael ministers accused Mr Ross of "showboating" on the issue and insisted the Transport Minister was ready to sign off on an appeal of the EU judgment at a Cabinet meeting on Wednesday.
However, Fine Gael sources said he backtracked on the decision when concerns were raised by Independent Children's Minister Katherine Zappone.
But the Independent Alliance this weekend hit back and branded Fine Gael "liars" and insisted concerns were raised by the group when a Dail motion agreed by the Cabinet was changed without their consent.
"Fine Gael's problem is they don't like any dialogue and just want it all their own way," a senior Independent Alliance source told the Sunday Independent.
The deteriorating relationship between Fine Gael and the Alliance will be brought into sharp focus in the coming weeks as Budget negotiations begin. A senior Cabinet minister said the latest row "does not augur well for the Budget".
"This is the first time since the Government was formed that a lot of people in Fine Gael are saying 'is it worth it' because the limitations of this particular minority Government have become apparent for all to see," the minister added.
Another minister said Fine Gael will soon "put a gun to Ross's head" and ask him if he wants an "election or to be in government?"