The controversial EU Reform Treaty will be officially signed by the Government at a ceremony in Lisbon on Thursday. The charter is expected to be put to a referendum in Ireland during 2008.
Government partners, the Green Party is holding a convention of its members in January to decide its official policy on the Treaty.
Sinn Fein president Gerry Adams yesterday urged people to oppose the Treaty because it will take power away from EU member states.
Meanwhile the 50th anniversary of the Treaty of Rome will be marked in Dublin tomorrow. Minister for Foreign Affairs Dermot Ahern will launch the publication 'Foundations of an Ever Closer Union' for the occasion.
The Treaty of Rome, which established the European Economic Community (EEC), came into force on January 1st, 1958.