(Adds Irish Prime Minister, background)
BRUSSELS, April 29 (Reuters) - European Union leaders promised on Saturday to embrace the British province of Northern Ireland into the EU if a referendum in the future were to unite it with the Republic of Ireland.
At a summit on the EU's plan for negotiating with Britain as 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.
European Union leaders gave their political endorsement to what Irish and EU legal experts say is the position in international law of such territorial changes.
"This is not about triggering any mechanism, ... the conditions for a referendum do not currently exist, but the acknowledgement of the principle, the potential, within the Good Friday agreement, is hugely important," Kenny told reporters after the summit.
Some EU officials said the declaration was a statement of "the obvious" and have stressed the summit was not taking a view on unification.
"The six counties (of Northern Ireland) remain part of the United Kingdom unless and until the people decide make a different choice by a democratic means in other words by a referendum," Kenny said.
Kenny said Britain, whose prime minister Theresa May was absent from the summit, has itself taken the same view on EU membership for Northern Ireland. Brexit minister David Davis acknowledged last month that, if it united with the Republic, it would be entitled to be absorbed into the EU.
UNIFICATION NOT IMMINENT
Calls for a referendum on leaving the United Kingdom have picked up since Northern Ireland, like Scotland, voted to remain in the EU, while the United Kingdom's two other nations, England and Wales, chose to leave in last year's Brexit vote.
Elections in Northern Ireland in March denied pro-British unionists a majority in the province for the first time since Ireland was partitioned in 1921, further emboldening Irish nationalists and their main political representatives Sinn Fein.
But Kenny has consistently said that now is not the right time for a vote and demographics suggest it could take a generation before Catholics, who tend to back Irish nationalist parties, become a majority among Northern Ireland's population.
Northern Ireland's future is part of broader uncertainty for territories of what was once the world's biggest empire.
Britain's right-wing press fulminated last month against EU plans to spell out that Spain, which claims sovereignty over Gibraltar, should have a veto over applying any future EU-UK free trade deal to the tiny British enclave.
Last week, Argentina said it thought it might gain EU backing after Brexit for its claim to the Falkland Islands, 35 years after losing a brief war there to Britain.
Closer to home, Brexit has fuelled calls to break away not only in Northern Ireland but also in Scotland. (Reporting by Jan Strupczewski; Editing by Ros Russell)