The Taoiseach has firmly rejected the SDLP's concerns about the proposed citizenship referendum, arguing that it creates "no difficulties" with the Good Friday agreement and claiming it is needed to close a "clear loophole" in Irish citizenship laws.
Mr Ahern said the Government had been advised on the implications of the referendum for both the Republic and the North, and was satisfied it had no effect on the Belfast Agreement or the rights of most children born in the North.
"A child born in Northern Ireland of a parent who is either Irish or British, or a non-national who has no restrictions on their stay, will get citizenship," he said.
The SDLP leader, Mr Mark Durkan, has said the proposed constitutional amendment borders on a "drive-by change to the Constitution and the Good Friday agreement".
Mr Durkan has argued that it is not in the gift of the Government to re-interpret or adjust the citizenship "promises" contained within the agreement.
The Taoiseach said yesterday he had already responded in detail to the SDLP's fears, but added that he was willing to give the party further briefings if required.
Mr Ahern said the referendum was on a simple issue. He described citizenship as "the essence of our sovereignty", adding that it automatically carried "rights and responsibilities".
"Citizenship is not just a matter of passport," he said, adding that the system as it stands is "wide open to abuse".
"It was never the intention that the agreement would be used as a means of abusing Irish citizenship laws," he said, referring to people wrongly seeking the "benefit of citizenship".
Mr Ahern said it would be "irresponsible" to shy away from dealing with the matter in a referendum, which is to be debated in the Dáil this week. Opposition parties have said they will table a motion asking for the referendum to be deferred.