Brussels - The European Union's Lisbon Treaty is not likely to be in place before European Parliament elections in June 2009, postponing some of its key reforms for at least five years, Luxembourg's influential prime minister said Wednesday.

"I do not think the treaty will be in place by June 2009," Jean-Claude Juncker said at a briefing with the European Policy Centre in Brussels.

The EU is grappling with the question of how to respond to Irish voters' rejection of the treaty at a referendum on June 12. The vote means the treaty cannot come into force anywhere in the EU unless the Irish government finds a way to ratify it, possibly by calling a second referendum.

In recent weeks a number of top officials have said they doubt the Irish government will find a solution before the end of 2009. Juncker said Wednesday that he thought the treaty could come into force "for January 1, 2010."

Irish Prime Minister Brian Cowen is expected to brief EU counterparts on the issue at a summit on October 15.

EU citizens are set to elect a new European parliament in June 2009, while member states are due to nominate a new European Commission by November 2009. Both parliament and commission sit for a five-year term.

If the Lisbon treaty is not in force, the elections will have to be carried out according to the EU's current rules, the Nice treaty.

That would mean an expanded parliament, with 785 members rather than the 751 foreseen in the Lisbon treaty.

It would also mean a smaller commission. At present the EU's executive body has one member per EU state, but the Nice treaty states that there should be "less than the number of member states."

Ironically, one reason Irish voters gave for rejecting the treaty was the fear of losing their national commissioner. The Lisbon treaty foresaw a commission cut in size by one-third - but only from 2014.

The Lisbon treaty is the successor text to the ill-fated EU Constitutional Treaty, which was brought to an ignominious end when Dutch and French voters rejected it in referenda in mid-2005.

EU leaders had promised that it would make the bloc more efficient and give it a higher profile in world affairs. (dpa)