Angry party members were responding to an opinion poll which shows the party is now on just 21% — a full 13 percentage points behind Fine Gael.
The Behaviour and Attitudes survey for The Sunday Times was the lowest rating for Fianna Fáil for two years, having fallen three points since the previous poll.
However, a number of party TDs gave voice to their anger on Saturday and accused Taoiseach Leo Varadkar of leaking details of his meeting with Mr Martin about extending the confidence and supply agreement.
The two leaders met in Killarney on Thursday night and, as reported in the media, Mr Varadkar requested that Mr Martin accede to a two-year extension to the deal.
“More games from the Taoiseach. So much for a private discussion leader to leader. Can’t help himself with the constant leaking & spinning. Agreement review will occur after the budget as set out,” said the party’s finance spokesman Michael McGrath on Twitter.
This drew a sharp response from Kilkenny TD and chair of the Oireachtas Finance Committee, John McGuinness, who said: “The Agreement review? 21%? Change direction or ask the people! Simple as!”
Robert Troy, the party’s spokesman on transport, also criticised Mr Varadkar saying: “Trust a man who leaks a private meeting to papers?? more interested in setting an agenda than constructively working to provide stability.”
However, this too drew a withering response from Mr McGuinness.
“Oh dear! How can Micheal ever trust him again, Robert? It must be so hard to support someone like Leo and his Gov that have an agenda and are planning ahead!” Mr McGuinness said, alluding to a sense of chaos in his own party.
Mr McGuinness is reflective of a growing unhappiness among party TDs over the ongoing deal, arguing the party is suffering as a result of it.
He was unable to comment when contacted by the Irish Examiner yesterday.
Responding last night, one senior party figure sought to dismiss Mr McGuinness’s comments, pointing to similar comments he made in 2014 just before the party became the largest party at local level and again ahead of the 2016 general election, where the party gained 23 seats.
Meanwhile, at the MacGill Summer School yesterday, former taoiseach Bertie Ahern said the “natural lifespan” of the Government support pact between Fianna Fail and Fine Gael ends next Easter, at which point an election may be called.