PRAGUE: Czech senators on Wednesday approved the European Union's troubled Lisbon Treaty, leaving an Irish referendum as the last major stumbling block to major reform of the bloc.

Members of the upper house in the country which currently holds the EU presidency, approved the treaty, which aims to streamline decision-making in the 27-nation group, by 54 votes to 20.

The treaty must be ratified by all 27 members to take effect. It now depends largely on Ireland, which will hold a second referendum by November, following its rejection by voters there last year.

But the Czech ratification still requires the signature of President Vaclav Klaus, a eurosceptic and fierce opponent of the treaty.

Klaus made it clear he was in no rush to ratify the document. The senators, had "turned their backs on the Czech Republic's interests," he said.

"The treaty is dead for the moment because one member state rejected it in a referendum. This is why a decision on the ratification of the treaty is not on the cards for me," he added.

Polish President Lech Kaczynski was also reluctant to sign the text despite its endorsement by the Polish parliament, saying he would wait for the Irish vote and then decide.

Senate chairman Premysl Sobotka said the government and parliament could not "wield any influence whatsoever on the president. He is free to decide as he wishes."

Despite the uncertainty however, the treaty's supporters welcomed the vote.

"This is very good news," European Commission chief Jose Manuel Barroso said in a statement.

"I am very happy at the approval today of the Treaty of Lisbon by the Czech senate, which completes the parliamentary process of ratification in the Czech Republic."

Alexandr Vondra, Czech deputy prime minister for European affairs, said the vote marked "an important day for the Czech Republic, for its position and influence in the EU and the world."

Foreign Minister Karel Schwarzenberg said the Czech Republic had "joined those countries that are determined to thoroughly follow the European path" with the vote.

At the European parliament, the head of the Socialist group Martin Schulz said the vote increased his optimism that the treaty could be ratified by the end of the year.

"It's good news, but it is not the end of the story," said the co-presidents of the Green group in parliament, Monica Frassoni and Daniel Cohn-Bendit.

"Lessons must be learned from the laborious way the treaty has been ratified," they added.

Austrian Foreign Minister Michael Spindelegger welcomed the vote and said it was "an important signal for the ratification (of the treaty) in Ireland."

The Czech Republic was the last member state to begin ratification. The lower house finally approved the treaty in February.

Klaus's allies in the ruling right-wing Civic Democrats (ODS) delayed the approval with lengthy speeches and postponements in parliament, even filing a constitutional lawsuit against the treaty.

Germany's parliament has approved the treaty but its ratification has also been stalled by a lawsuit brought before Germany's top court.