At a summit called to agree the EU's plan for negotiating with Britain at it leaves the bloc, Irish Prime Minister Enda Kenny asked fellow members to acknowledge that Northern Ireland would, like East Germany in 1990, automatically enter the EU in the event of unification with existing member state.
The 1998 Good Friday Agreement to end violence in Northern Ireland foresees the holding of referendums on both sides of the border on uniting the island if London and Dublin see public support for that.
EU leaders gave their political endorsement to what Irish and EU legal experts say is the position in international law of such territorial changes.
(Reporting by Jan Strupczewski, Editing by Robin Pomeroy)
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