The results in full | The reaction

The future of the European Union was tonight clouded in uncertainty after Ireland voted No to the Lisbon Treaty.

Jose Manuel Barroso, European Commission President, and a raft of foreign ministers expressed dismay that Ireland - the only member state to hold a referendum on the matter - chose to reject it decisively by 53.4 per cent to 46.6 per cent.

Amid wild cheers from No campaigners, the results were revealed at 5pm with 862,415 votes against and 752,451 in favour, giving a majority of 109,964 against.

Despite the result, EU leaders were tonight vowing to press ahead with ratifying the treaty.

However, the Lisbon Treaty - the reworked successor to the formal constitutional pact dumped by voters in France and the Netherlands in 2005 - officially needs the approval of all 27 EU member states, meaning the way forward for the union is now uncertain.

Mr Barroso said he believed that other states should press ahead with the ratification process. "The no vote in Ireland has not solved the problems which the Lisbon Treaty is designed to solve," he said.

"The ratification process is made up of 27 national processes. Eighteen member states have already approved the treaty and the European Commission believes that the remaining ratifications should continue to take their course."

In a joint statement, President Nicolas Sarkozy of France and Angela Merkel of Germany backed him, saying: "We take note of the democratic decision of the Irish citizens with all due respect, even though we regret it," adding that they "hope that the other member states will continue the process of ratification".

However, there was uncertainty among some member states as to how the EU could still bring a treaty into force by January 1, 2009.

In a television interview last night, Francois Fillon, French Prime Minister, appeared to indicate that a No vote could scupper the treaty all together. "If the Irish people decide to reject the treaty of Lisbon, naturally, there will be no treaty of Lisbon," he warned.

Commentators said that the results were a personal disaster for Brian Cowen, the newly appointed Irish Prime Minister, who has struggled to rally the Yes vote following a surprise last-minute surge in opinion poll support for the 'no' campaign in the past week.

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