Finance Minister Brian Lenihan accused the Taoiseach of a lack of judgment today as he reignited controversy over the so-called "gargle-gate" radio interview.
Despite pledging his support for Brian Cowen, Mr Lenihan openly attacked his leader and revived six-month-old allegations that he sounded hungover in a live broadcast.
The minister, who denied marshalling a plot to take over the ruling Fianna Fail party, also hit out at the Taoiseach's contacts with Anglo-Irish Bank bosses as it neared collapse.
The two affairs are low points in Mr Cowen's last six months in office and Mr Lenihan said he was unhappy with both controversies.
"The Taoiseach has had his difficulties," Mr Lenihan said.
"I'll make no secret of the fact that I was not happy with what happened in Galway in connection with the interview and the recent developments in relation to a certain golf game he had.
"I think they showed lapses of judgment."
Mr Cowen was last week forced to account for social meetings with senior Anglo officials after previously undisclosed contacts were revealed - a golf game and dinner at the Druid's Glen resort in Wicklow and a direct phonecall with bankrupt ex-Anglo chairman Sean FitzPatrick from Malaysia in 2008.
He has denied the meetings influenced in any way the crippling State-backed bank guarantee scheme introduced in September that year.
The damaging contacts were detailed by Mr FitzPatrick in a new book.
In a separate controversy, the Taoiseach denied he was drunk or hungover during a live morning radio interview after a Fianna Fail party get-together in a Galway hotel last September. Mr Cowen said the allegations were a pathetic stunt and a new low for politics.
Senior ministers defended their leader at the time, claiming he had been hoarse and groggy.
It later emerged the Taoiseach had enjoyed a late night with TDs and Senators as they held a two-day think-in to prepare for the return of Dail.