The Tory leadership has conceded defeat over plans to hold a referendum on the Lisbon Treaty.
Shadow foreign secretary William Hague said yesterday it was not possible to hold the vote after Czech President Vaclav Klaus removed the last obstacle to full ratification.
He said: “Now that the treaty is going to become European law, a referendum can no longer prevent the creation of the president of the European Council.”
Mr Hague said party leader David Cameron would today set out “how we will go forward in European matters”.
He also denied the party had broken their promises by dropping the referendum pledge.
Earlier, Eurosceptic Mr Klaus announced he had signed the treaty after the Czech Constitutional Court rejected an attempt to block its implementation.
The move threatens to throw the Tories into renewed turmoil over Europe.
The Conservative leadership has been signalling that it would not be able to go ahead with a referendum if the treaty was ratified.
However, for Tory Eurosceptics it has become an article of faith after Mr Cameron gave a “cast-iron guarantee” he would give Britons a chance to vote on the treaty. He is now expected to announce a general election manifesto commitment to “repatriate” powers from Brussels, including control of social and employment policies – a long-standing Tory aim.
Foreign Secretary David Miliband denounced Mr Cameron's position as “false and dangerous”.
“So much for David Cameron’s guarantee to hold a referendum on the Lisbon Treaty,” he said. “He is not being honest with people. The fact is you can’t simply opt out of treaty obligations.”
Business Secretary Lord Mandelson said: “Cameron’s cast-iron guarantee has become very rusty indeed.”
UK Independence Party leader Nigel Farage said: “Mr Hague says it is ‘no longer possible' to have a referendum. Well, to me and millions of others it is apparent that it is no longer possible to trust the Tory party or David Cameron when they make promises about Europe.”
Eurosceptic Tory MP Bill Cash said he had written to Mr Cameron urging him to “reconsider” his decision not to hold a referendum, saying the leader had been “badly advised” and insisted the issue can still be put to a vote.
Prime Minister Gordon Brown welcomed the completion of the Treaty ratification process.
It is now expected that a meeting of the European Council will be called by Sweden, which holds the presidency, to discuss the appointment of a president and high representative for foreign affairs, as well as a new European Commission.