"Last week we saw a lineup of government ministers from Fianna Fail, the Greens and the PDs saying that they believed the unbelievable and that they accepted the unacceptable. As in times past with Fianna Fail leaders under pressure facing investigation, cabinet colleagues have put positions before integrity and false loyalty before public service, " Kenny told the Sunday Tribune.

Describing the three-party government as a "mongrel of a coalition", he said it was "poorly conceived" and already "showing strains after just one week back".

He was withering in his assessment of the Greens, claiming it was "obvious that they were bought off with a bargain basement deal and last week proved that they will stay bought".

Kenny's comments come in the wake of statements from Labour leader Eamon Gilmore who said, "The week just gone represented the worst start to a parliamentary term by any new government since the days of the Haughey and Gubu administration."

Green Party leader and environment minister John Gormley yesterday hit back at Gilmore's accusation that the Greens had engaged in "an extraordinary abdication of responsibility" on the issue of standards in public office.

Gormley said Gilmore's statement "reflects his own and his party's frustration and disappointment at the election outcome".

"If Labour and Fine Gael adopted similar standards, they arguably would not exist.

We are the only party which does not accept donations from business, " he said.

Meanwhile, the Taoiseach's plan for Brian Cowen to automatically succeed him is unlikely to be realised with foreign affairs minister Dermot Ahern this weekend making clear his interest in the top Fianna Fail job.

"Potentially there were many people in the party who could step into the shoes of Bertie Ahern, " said Ahern, in what is a pointed rebuff of the Taoiseach's public endorsement of Cowen as his "obvious successor".

Ahern declined to directly rule himself in or out of a leadership contest. But his remarks left enough room to send a clear signal to his parliamentary colleagues that he will be a contender.

"I am not going to say I don't have any aspirations, " he said. "The day any politician would say they didn't want to be leader of their party is the day they are gone."

Few deputies including Ahern anticipate an early vacancy. "The Taoiseach has said to me privately that he'll be around for a long time to come, " Ahern said. "Who is to say what will happen in two or three or four years' time?"

Cowen has increasingly been taking up what have been seen as "leadership positions" within Fianna Fail.

However, several other cabinet ministers have expressed surprise that Cowen is a foregone conclusion.