Foreign affairs minister Micheal Martin resigned from the Irish cabinet, claiming he could no longer stay in office after his failed revolt.
Despite voting against Brian Cowen in the confidence motion Mr Martin said the Taoiseach had his full support as head of government and into the looming general election.
"I have the basic view that if you come out as publicly as I did and lead in the manner that I did in a certain direction and spoke against the Taoiseach in that manner, the leader of the party, and cast a vote against him in a vote of confidence, I think that is incompatible with staying in an office," Mr Martin said.
"I've said this to the taoiseach and I just think it is a fundamental principle that one has to adhere to and that's why I have taken this course of action."
He said it was the honourable course of action, adding that he spoke to the Taoiseach in person and said Mr Cowen understood the motivation behind his decision.
He said he did not regret taking a stand against Mr Cowen's leadership.
"One has to make a stand and one has to force the issue in terms of debate," he said. "I think it has been a very healthy debate and a very good debate."
He claimed he did not try and get support from other cabinet ministers for his stance.
Mr Martin tabled his resignation on Sunday after Mr Cowen announced he had tabled a motion of confidence in himself after consulting with TDs and senators.
He claimed party members across the country did not want the Taoiseach as Fianna Fail leader in the general election, adding that the very survival of the party was at stake.