BRUSSELS, November 4 (RIA Novosti) - The EU's Lisbon Treaty, now ratified by all 27 member states, will come into force on December 1, the prime minister of Sweden, which holds the rotating EU presidency, has said.

On Tuesday Czech President Vaclav Klaus signed the document after the country's Constitutional Court ruled that the ambitious reform treaty was in line with the Czech Constitution.

"With the signature of the Czech President, all EU member states have now ratified the text," Fredrik Reinfeldt said in a statement. "The Treaty enters into force on December 1 and all the details must now be put into place."

Reinfeldt said he would call a summit of EU leaders as soon as possible and start consultations on candidates to become new European commissioners.

The agreement was drafted in the Portuguese capital on December 13, 2007, and introduces fundamental changes to the workings of the European Union.