Taoiseach Bertie Ahern said he favoured holding the EU treaty and children's referendums on the same day.
He said that all parties had given a commitment on the issue.
"At the beginning of the year, the party leaders gave a commitment to the NGOs, and those associated with the children's issue, that we would hold the referendum within one year, if it was possible to do so, but it may not be.
"The members of the all-party committee are unanimous in the view that they need until the end of April or the other side of Easter to complete their work. A referendum Bill will then be required. We will have to see whether it is possible to link the two referendums."
Mr Ahern said that after this week they would have a commitment to deal with the EU reform treaty by January 1st, 2009.
"I will get formal advice from the Attorney General. It is obvious that there will have to be a referendum. We will talk to the Opposition leaders to see how the matter can be progressed."
Jim O'Keeffe (FG, Cork South-West) said he strongly supported the EU reform treaty and underpinning children's rights in the Constitution.
There would, however, be opposition to both, with most of "the usual suspects" lining up against any progress in Europe, and, no doubt, some would oppose putting children's rights into the Constitution, saying that it undermined family rights.
Mr O'Keeffe warned that a combination of those lobbies could endanger both proposals, and he cautioned against holding the referendums on the same day.
Mr Ahern said that they would have to make the judgment soon.
"Deputy O'Keeffe will agree, however, that one of the big problems surrounding EU referendums is to bring out a respectable size of electorate. We must make a call on this. The issues are beginning to crystallise quite well."
Labour leader Eamon Gilmore said that while he understood the Taoiseach's preference to hold both referendums on the same day, he wondered could he take it that this was now unlikely to happen, given the timetable the committee has set for itself.
Mr Ahern said it was still possible that the two referendums would be held on the same day.
"It might mean changing the timescale slightly, but it is possible. I will discuss the matter with the party leaders to see what can be done. It might not be possible to have both referendums in May, but it is still possible to have them on the same day. We can discuss the matter. I have an open mind on it; I do not really mind which way we do it."
Asked by Mr Gilmore if there was any doubt about the need for a referendum on the treaty, Mr Ahern replied: "There is no doubt about that."
Fine Gael leader Enda Kenny said he would be happy to speak to the Taoiseach about his views on fixing a timescale for the process.
"It is important that we get a fix on it. It will be difficult for the committee to do its work within a tight timescale. I am not sure it will be able to produce a report, a wording for the referendum and legislation to give effect to the referendum by May or June."
Asked about reform of the Seanad, Mr Ahern said that a constitutional referendum would definitely be needed if it was to be reformed in a broad manner.
A referendum would not be needed to allow the large proportion of people under the age of 35, who were graduates, to vote in Seanad elections.
