European Union leaders plan to guarantee respect for Irish military neutrality in a declaration next week aimed at persuading voters to back a major EU treaty they rejected last year, diplomats said.

The June 21-22 EU summit in Seville will issue a three-point declaration safeguarding Irish neutrality, assuring Dublin that it will not be expected to join a military alliance and pledging respect for Dublin's constitutional decision-making procedures.

Irish voters rejected the Nice Treaty on expanding the EU in June 2001.

The Irish government has identified neutrality as an issue that harmed the "yes" camp in the 54-46 per cent defeat of a referendum to ratify the Nice accord, which includes plans to create an EU rapid reaction force and its relations with the North Atlantic Treaty Organisation.

The treaty will expire if it is not signed by all EU members by the end of 2002, vastly complicating the admission of 12 new states, mostly from Eastern Europe.

Irish Prime Minister Bertie Ahern, determined to win the vote on the treaty expected in October, requested the statement in talks with Spanish Prime Minister Jose Maria Aznar last week.

"I hope, with the help of the prime minister, to get agreement that Ireland's traditional policy of military neutrality is not, will not, and cannot be affected by the Nice treaty or any other European Union treaty," Ahern said after that meeting.

Despite Ahern's comfortable re-election last month, opinion polls show an Irish endorsement of the treaty is by no means assured. Many voters fear enlargement will remove generous EU regional aid from Ireland.

Spain, which currently holds the EU's rotating presidency, has drafted a statement that aims to reassure the three million Irish that they will have no entanglement with NATO, which has a mutual defence clause, the diplomats said.

"It will be a political message reassuring the Irish and insisting on the importance we attach to their vote for the Nice treaty," one said.

The European Commission has said a second Irish "no" would delay the accession of up to 10 east European and Mediterranean candidate countries and cause a crisis of confidence in Europe.