Mattie McGrath's comments come as another day of negotiations between Independents and Fine Gael gets underway at Government Buildings.
Fianna Fail has also decided to hold round table talks with Independents TDs next Monday and Tuesday.
Deputy McGrath, says realistically the two big parties have to talk to each other, and soon.
Meanwhile Fine Gael has committed to holding a Citizens Assembly on the issue of the 8th amendment.
The party is not now expecting to finalise negotiations with Independents until next Monday, when Fianna Fáil is also set to begin negotiations with the Independents.
Elsewhere, two independents who have not been involved in talks with Fine Gael are to meet Fianna Fail later today.
Dublin Fingal TD Clare Daly and Wexford Deputy Mick Wallace have agreed to meet the party which will seek their support for Micheal Martin's nomination as Taoiseach.
It's not yet known what position the two will take on round table talks to be held by Fianna Fáil next week.
