June date for Irish EU referendum

A 'No' vote could stop the treaty coming into force in 2009

Irish Prime Minister Bertie Ahern says the vote on the Lisbon Treaty will be held in the second week of June.

He told the Dail - the lower house of parliament - that a final decision on a date was still to be made.

"The government have more or less signed off on the date. It is really a question about the day of the week".

Ireland is the only member state planning a vote on the treaty which reforms the EU's institutions and replaces the ill-fated EU constitution.

In 2001, Irish voters created a problem for Brussels by rejecting the Nice Treaty although they approved it the following year.

A vote against the Lisbon Treaty would jeopardise efforts to bring it into force in January 2009 as it has to be ratified by all 27 member states.

A number of national parliaments have already voted in favour of the document which was first endorsed by Hungary.

In Ireland, the treaty has the support of both the government and opposition but it is opposed by Sinn Fein. Recent opinion polls suggest voters will back the treaty with almost a third undecided.

Opposition leader Enda Kenny said the failure to name a specific date was "adding to confusion" about the referendum.