Stockholm - The Swedish parliament ratified the European Union reform treaty late Thursday after a nine-hour debate.

The Lisbon Treaty was approved by 243 legislators while 39 voted against. Thirteen members of the 349-seat legislature abstained while 54 members did not attend the vote.

EU Affairs Minister Cecilia Malmstrom, who had urged legislators to ratify the treaty, said it contained "new rules" and offered a "more efficient and open EU."

Rejecting the treaty would mean that Sweden would have "poorer means of influencing decisions" and would lose its say, Malmstrom said.

Birgitta Ohlsson, member of Malmstrom's Liberal Party, earlier said the treaty would make the EU more up-to-date.

Five of the seven parties in the foreign affairs committee a week ago supported approval of the Lisbon Treaty in accordance with the government's recommendation.

In addition to the four parties in Prime Minister Fredrik Reinfeldt's ruling coalition, the treaty was also supported by the opposition Social Democrats even though eight of its members abstained.

Sven-Erik Osterberg of the Social Democrats, a former cabinet member, opened the debate saying it was "necessary to cooperate over borders."

He added that his party wanted the EU to avert social dumping, the practice of importing goods from countries with weak labour standards.

The EU-sceptical Left Party and the Green Party oppose the treaty, but their 41 combined votes were not sufficient to prevent the ratification in the 349-seat legislature. They needed 59 votes to form a blocking minority.

Leftist Hans Linde compared the treaty to "Frankenstein's monster," citing the numerous efforts "to patch it up," and said previous no votes in the Netherlands, France and Ireland should be respected.

The Lisbon Treaty is aimed to streamline decision-making in the bloc but cannot enter into force until all member states have ratified it. Ireland, where voters rejected it earlier this year, has yet to decide on a possible new vote.

Sweden is due to take over the six-month rotating EU presidency in July 2009. (dpa)