The Lisbon Treaty could come into force as early as next month after Czech president Vaclav Klaus signed the charter earlier today, removing the last obstacle to its ratification.

Mr Klaus was the last EU leader to ratify the treaty and his signature means the union of nearly half a billion people can now focus on picking its first president and a more powerful foreign representative to speak for it on global affairs.

The treaty, with roots in the failed European Constitution rejected by voters in two member states in 2005, is aimed at making the European Union more flexible and a stronger player on the world scene, to match the rise of emerging powers like China.

The staunchly eurosceptic Czech president signed the pact after the country's Constitutional Court had thrown out a complaint against it earlier in the day.

"I had expected the court ruling and I respect it, although I fundamentally disagree with its content and justification," Mr Klaus told reporters.

The European Union's Swedish presidency said it would like all remaining details to be put in place so that the treaty could come into force on December 1st.

Swedish prime minister Frederik Reinfeldt said he would call an EU summit to discuss possible appointments under the treaty.

European Parliament president Jerzy Buzek said President Klaus's signing was "great news". Governments should now get on with nominations for the new posts as quickly as possible, he said.

EU leaders failed to agree at a summit last week in Brussels on who should hold the new EU presidency, a post whose powers are still somewhat unclear.

The chances of once-favoured Briton Tony Blair, the former prime minister, seem doomed after he failed to win the backing of the European Socialists, his Labour Party's allies.

No front-runner has emerged, but possible contenders include former taoiseach John Bruton, Dutch prime minister Jan Peter Balkenende, former Finnish prime minister Paavo Lipponen and Luxembourg prime minister Jean-Claude Juncker.

The Czech president had been banned by law from signing the treaty until the Constitutional Court had ruled on a complaint by his allies in the Czech upper house, the Senate, who argued the treaty would erode national sovereignty.

The court rejected the arguments. "The judgment was unanimous; none of the judges filed a dissenting opinion to either the judgment or its reasoning," the court said in a written verdict.

The Czech parliament has approved the pact but president Klaus long argued against it, saying it would turn the bloc into a superstate with little democratic control.

"With the Lisbon Treaty taking effect, the Czech Republic will cease to be a sovereign state, despite the political opinion of the Constitutional Court," he said.

He had said he would raise no further obstacles after EU leaders agreed last week to give the Czechs an opt-out from a rights charter attached to the treaty. President Klaus says this was necessary to avoid property claims by Germans expelled from Czechoslovakia after World War Two.

Reuters