British opposition leader David Cameron renewed his pledge last night to hold a referendum on the EU's reform treaty if he wins power next year and the treaty has still not come into force.
Ireland has ratified the treaty, leaving the Czech and Polish leaders as the only heads of state that have yet to sign the document before it can take effect.
"There will be no change in our policy on Europe. There will be no change in Conservative policy as long as the Lisbon Treaty is still not in force," said Cameron, who leads the centre-right Conservative party, widely tipped to win a parliamentary election due by next June.
"I have said repeatedly that I want us to have a referendum. If the treaty is not ratified in all member states and not in force when the election is held, and if we are elected, then we will hold a referendum on it." The British parliament ratified the Lisbon treaty after the Labour government rejected Conservative calls for a referendum.
The Conservatives say they will reverse Britain's ratification if voters reject it in their planned poll. William Hague, the party's foreign affairs policy chief, said he respected Ireland's decision, but said the treaty had "no democratic legitimacy" in Britain.
"The government now needs to explain why the Irish people have had to vote twice when the British people have not been allowed to vote once," he said.
Despite the convincing Irish vote, Mr Cameron said he would name a referendum date during the election campaign.
While the Polish president looks set to the sign the treaty soon, a challenge at the Czech Constitutional Court has halted Prague's ratification process for now. However, the Czech prime minister believes the president will sign by the end of the year.
"The Czech prime minister has said that the constitutional challenge before the Czech Constitutional Court could take three to six months to resolve," Cameron said.
Mr Cameron also said that even if the treaty, designed to speed up decision-making, were ratified by all members, the Conservatives would continue to fight it.
The Tory leader is mindful some Conservative right wingers want a referendum even if all EU states have ratified it.
A survey of 2,205 party members undertaken by the ConservativeHome.com website for the Independent newspaper on Saturday found that more than eight in 10 supporters want him to call a referendum even if it is approved.
PA