Fianna Fáil leader Micheál Martin has accused Taoiseach Leo Varadkar of being "the one person" creating instability in Government.
He said Mr Varadkar had created that aura of instability. "It's all coming from Fine Gael. It's not coming from me."
Mr Martin also said he could not understand why the Taoiseach appeared to be keeping open the option of collapsing his own Government.
Speaking on the This Week programme on RTÉ Radio One, Mr Martin said he had, in the wake of the resignation of Denis Naughten as Minister for Communications last week, asked Mr Varadkar to join him and agree that neither party would collapse the Government while the Brexit talks were ongoing.
To do so, Mr Martin said on Sunday, would be “reckless and irresponsible”. Mr Martin said the process of a review of the three-year confidence-and-supply agreement, which ends with Budget 2019, had begun but he also said it was important that the Government remain stable and in a position to deal with Brexit.
The Fianna Fáil leader said that Brexit was “more serious than the interests of any individual or party”.
He said any deal would have to be ratified by the British parliament in January and if it was rejected the Republic might find it had to support Article 50.
But Minister for Justice Charlie Flanagan disagreed with this view and said “by doing that we concede the idea that the Irish Government could fall on the basis of a vote of the British parliament”.
Mr Flanagan said the “best way to ensure no election is to renegotiate the confidence-and-supply right out until 2020”.
Mr Martin said both he and the Taoiseach had agreed that there should be no preconditions to the review of the confidence-and-supply agreement between the two parties.
Mr Martin and Mr Varadkar are to meet next week to discuss the future of the deal. In a letter on Friday, Mr Martin proposed that they both commit to not collapse the Government until a final Brexit settlement had been reached.
In response, Mr Varadkar has said a full renegotiation of the confidence-and-supply agreement, with a commitment to a summer 2020 election, could be wrapped up within a month.
Mr Martin said the National Broadband Plan had been “hopelessly compromised”.
Mr Martin also said there were issues about the capacity of the remaining bidder in the tendering process for the contract worth up to €500 million to provide broadband to 540,000 homes and businesses that cannot access it through the normal process.
“I think we’re going to have to make sure it’s done right”.
He said there was an assessment being conducted but “it seems to be me that it has been hopelessly compromised unless someone can prove otherwise”.
Speaking to RTÉ, Mr Martin said that the plan was compromised “because of the fact that Minister who is the ultimate decision-maker met the businessman” leading the bid at a number of private meetings.
Expressing concern about the remaining bid, Mr Martin said “it’s now being led by an investment fund”.
He said “the composition of the final bidder is demonstrably very different” from what it was originally.
The loss of Mr Naughten and, the previous week, Peter Fitzpatrick’s support, has undermined the stability of the Government.
In a move to shore up the Government’s voting strength the Taoiseach has secured the support of Independent TDs Noel Grealish and Michael Lowry.
Galway West TD Mr Grealish said he made the decision following a meeting with Tánaiste Simon Coveney and a lengthy conversation with Mr Varadkar over the weekend.
Mr Grealish said: “Ireland is now entering one of the most critical and uncertain phases since the foundation of our State and it is in the best interests of our country as a whole that we have a stable Government at this crucial time.”
Mr Naughten’s departure from Government had reduced the number of votes the Taoiseach could command in the Dáil to 55 – two short of a bare majority when Fianna Fáil abstains.
However, securing the support of Seán Canney – who was given a junior minister portfolio on Saturday, Mr Grealish and Mr Lowry gives the Government a voting strength of 57, when the Independent Alliance and Katherine Zappone are included.
Mr Lowry told The Irish Mail on Sunday it would have been unpatriotic for him to have not pledged support for the Government giving the importance of Brexit. He said he would vote in favour of the Ministerial appointments announced by the Taoiseach on Saturday which saw Richard Bruton replacing Mr Naughten as Minister for Communications.
Mr Lowry also denied he had asked for anything specific in return for his support.
“I didn’t ask for anything in return. I am happy with the access I have to the Government and to Government departments ...”
