A coalition between Fianna Fáil and Fine Gael would be "thwarting the wishes of the electorate" and result in a "same-old, same-old" government it has been claimed.
Senior Fianna Fáil TD Éamon Ó Cuív made the remarks as he set out why he is "totally opposed" to a deal between Micheál Martin and Taoiseach Leo Varadkar.
Mr Ó Cuív was among Fianna Fáil Tds who spoke out against the prospect of such an arrangement at a private meeting of the Fianna Fáil parliamentary party yesterday.
At the meeting the party agreed to rule out a deal with Sinn Féin and to seek talks with all other parties.
Today Mr Ó Cuív told Independent.ie that he accepts that Fianna Fáil won't go into government with Sinn Féin.
But he added: "I am totally opposed to Fianna Fáil and Fine Gael effectively thwarting the wishes of the electorate by going into government and giving the same-old, same-old."
Mr Ó Cuív said that Fianna Fáil has ruled out a coalition with Sinn Féin and that the only remaining proposal on the table would be a coalition with Fine Gael and the Green Party.
"I feel that that should be rejected," he said.
Mr Ó Cuív said that if it is rjeected "we have to start thinking it all out again. It will be the 160 members of Dáil Éireann that will have to think again."
He said that while he respects all of the other TDs in the Dáil his reason for being opposed to the Fine Gael option is that he does not agree with their "conservative policies".
Asked if he would serve as a minister in such an administration, Mr Ó Cuív said: "We haven’t got as far as that. I’m not presuming that Fianna Fáil will endorse this."
He said his understanding is a coalition with Fine Gael would have to be put before a Fianna Fáil Ard Fheis for members to have their say.
Elsewhere, Sinn Féin leader Mary Lou McDonald spoke about the prospect of a deal between Mr Martin and Mr Varadkar saying it is "farcical" to suggest that Fianna Fáil and Fine Gael together represent change.
She said: "I think it is actually quite disgraceful that the old boys’ club of Fianna Fáil and Fine Gael believe that they can set aside the democratic mandate of Sinn Féin.
"I have no sense of entitlement to anything but I can tell you this much, the people who vote for us, the people who represent hundreds of thousands of them are entitled to respect."