LUXEMBOURG – France performed a historic about-face yesterday and abandoned the E.U. constitution to its fate, dropping demands that other nations ratify the treaty.

The unexpected move appeared to seal the constitution’s doom, even if its most passionate supporters still refuse to accept its demise for several months more. Days before a crisis E.U. summit, the French foreign minister, Philippe Douste-Blazy, simply waived Paris’s insistence that the treaty still be put to the vote, country by country.

“Our humble and modest position says we simply respect the position of each member state,” Mr. Douste-Blazy said.

He added that it was not up to France to “dictate” how others should proceed, but then raised the stakes in the battle over the E.U. budget by accusing Britain of selfishly refusing to pay the bill for enlargement last year, when 10 nations joined the European Union.

Senior French officials quietly agreed with British predictions that an E.U. summit this week would leave individual member states to decide how, or whether, to vote on the constitution, with no deadline or timetable. Without these “the whole thing is being kicked into some very long grass indeed,” one E.U. official said.

“You could say it is effectively dead.”

A senior French official said: “The heads of state prefer to avoid a debate on the timetable.”

An original deadline of November 2006 was now “a target date, a date on which we take stock,” the French official said.

Britain’s foreign secretary, Jack Straw, maintained pressure on France to clarify whether it feels capable of holding, and winning, a second vote on the constitution.

If France says it has no hope of reversing its first “no” vote, the treaty is effectively dead, because it must be ratified by all 25 member states.

Speaking at a meeting of E.U. foreign ministers in Luxembourg, Mr. Straw said: “There is a general consensus that decisions on whether to proceed with ratification or not should be left to individual member states.”

France would be asked to make clear at the European Council on Thursday “how they intend to proceed,” Mr. Straw added.

The apparent demise of the E.U. constitution plunges Europe into its deepest political crisis for decades.

The drafting of the text took four years of intense negotiation. It was born after E.U. leaders agreed that the spider’s web of overlapping treaties was not fit to govern life in the new, greatly expanded European Union of 25 nations, soon to rise to 27 with the addition of Romania and Bulgaria in 2007.

France led calls for it to be called a “constitution” and its drafting was presided over by a former French president, Valery Giscard d’Estaing.

Its overarching aim was to streamline the process of taking decisions and to create a new E.U. presidency and foreign minister.

France, which first threw the project into question with its “no” vote on May 29, had been in the vanguard of moves to keep the treaty alive. President Chirac had repeatedly called on other states to carry on with referendums or parliamentary votes.

Desperate to avoid being the “black sheep” of Europe after a “no” vote, Mr. Chirac allied himself with 10 nations that had ratified the text.

His government endorsed a contentious argument that all nations were obliged to hold votes before a November 2006 deadline – a regulation federalist leaders claimed to find buried deep in the text.

That position has abruptly collapsed, helped by hints from countries such as Denmark, the Czech Republic, and Poland that they had no appetite for holding referendums, with opinion polls predicting a long string of “no” votes.

The Netherlands – whose June 1 referendum three days after the French vote delivered an even more emphatic “no” – has been conspicuously silent on the subject.

The Dutch government tersely declared it had heard the voice of its voters, and would not now send the constitution to parliament for formal ratification.

The final text that emerges from the European Council is, nonetheless, unlikely explicitly to declare the constitution dead. Many pro-constitution leaders are pushing for a “freeze” or a “pause for reflection” in the hopes of resurrecting the treaty later.

One E.U. official said: “No one is ready to kill this thing off, but an open-ended deadline is a tacit admission that this thing is in serious difficulties. That might be combined with a freeze.”

However, the Danish foreign minister, Per Stig Moeller, hinted that his government – which privately longs to postpone or scrap a planned September 27 referendum – had serious doubts about a pause, in case others tried amending the treaty while it was in the deep freeze.

Denmark needed a clear plan to emerge from the European Council, if it was to hold a vote on the treaty, Mr. Moeller said.

Emerging from two days of talks with fellow ministers, he concluded: “The conversations I had don’t convince me we will get a clear answer.”