Former Minister Éamon Ó Cuív claims many Fianna Fáil members would have 'huge issues' with forming a government with Fine Gael and the Greens.
The three parties are holding talks today to see whether they can put together a coalition.
The discussions are likely to continue for the rest of the month, with carbon emissions remaining a big issue.
Last week, Fianna Fail councillors in Donegal wrote to party leader Michael Martin expressing their opposition to a coalition with Fine Gael.
Galway West TD Éamon Ó Cuív says many other Fianna Fáil members share the Donegal view, and also have questions about the Green Party.......