Brussels  - The head of the European Commission, Jose Manuel Barroso, is set to hold crisis talks with EU leaders after Ireland voted to reject the bloc's Lisbon treaty, officials confirmed Friday.

"Over the coming days, President Barroso will undertake consultations" on how the EU should proceed, a press release said.

EU foreign ministers are due to meet in Luxembourg on Monday, the commission - the EU's executive - and European Parliament are set to meet in Strasbourg on Tuesday, and EU heads of state and government are due to gather in Brussels on Thursday.

Barroso's consultations are set to take in representatives of the EU's member states, the president and party leaders of the European Parliament and the members of the commission itself, his spokesman told Deutsche Presse-Agentur dpa.

Ireland's rejection of the Lisbon treaty, which is designed to make the EU more efficient and comprehensible to voters, means that the treaty cannot now come into effect, even though parliaments in 18 member states have already voted to ratify it.

As the news of the vote broke, Barroso said that the commission "would have hoped for another outcome," but would respect the outcome of the referendum.

But the result has already sparked debate across Europe on how the 27-member bloc should now proceed, with European heavyweights such as Germany's Chancellor Angela Merkel and France's President Nicolas Sarkozy urging the remaining eight member states who have not yet ratified to do so. (dpa)