By Adrian Croft and Justyna Pawlak
VILNIUS (Reuters) - France, which backs military action to punish Syria for a deadly chemical weapons attack, tried to rally support from its European Union partners on Friday but met scepticism from governments wary of turning their backs on the United Nations.
French Foreign Minister Laurent Fabius sought agreement from EU counterparts meeting in the Lithuanian capital Vilnius that President Bashar al-Assad's government was responsible for an August 21 gas attack that the United States says killed more than 1,400 people, a source close to Fabius said.
But he was rebuffed by German Foreign Minister Guido Westerwelle and other ministers who said countries contemplating military action must await the findings of U.N. chemical weapons inspectors, which could take weeks.
After British Prime Minister David Cameron failed to win parliamentary backing for military strikes, France is the only major military power lining up behind U.S. President Barack Obama, who is seeking a go-ahead from Congress.
Some EU nations oppose a military strike, making it hard for the 28-nation bloc to forge a common position.
U.S. Secretary of State John Kerry is due to join the EU ministers in Vilnius on Saturday to discuss Syria and the Middle East peace process.
"We believe that it is necessary to wait for the report of the U.N. chemical weapons experts before taking any further decisions, also on possible measures of a military nature. That's our appeal to those who talk and think about military measures," Westerwelle told reporters in Vilnius.
Germany had urged U.N. Secretary-General Ban Ki-moon to speed up publication of the report, Westerwelle said.
He also said Germany was in "extraordinarily close talks with the Russians" to try to make progress on the diplomatic track. Divisions between Western powers and Russia and China have blocked effective action in the U.N. Security Council to resolve the 2-1/2-year-old Syrian conflict.
On arrival in Vilnius, Fabius played down the U.N. inspectors' report, saying it was likely to disappoint, because the inspectors had only been asked to look into whether it was a chemical attack, not who was responsible for it.
But French President Francois Hollande said later in St. Petersburg, Russia, that France would await the conclusions of the inspectors before deciding on action.
Swedish Foreign Minister Carl Bildt said their findings would be very important for giving "international credibility for whatever happens".
Several other ministers made clear they believed the United Nations should be in charge of efforts to find a solution to the crisis. The EU has been scarred by the experience of a decade ago when a U.S.-led coalition invaded Iraq without U.N. backing.
"As far as my government is concerned, the United Nations should be put in a position to draw conclusions on the basis of the reports given by the inspectors," Dutch Foreign Minister Frans Timmermans said.
Luxembourg Deputy Prime Minister Jean Asselborn said many EU countries faced a "practically impossible" choice between the position of the United States and France and the basic rules of the United Nations.
"We must not forget the political solution before attacking, because once you have struck, the political solution becomes enormously difficult," he said. "Is it really in the interests of the Syrian people to want to punish Bashar al-Assad through military strikes? I think not."
At a summit of the Group of 20 countries in St. Petersburg this week, the EU's top officials stopped short of endorsing the U.S.-led push for a military strike on Syria and warned there could be no military solution to the conflict.
(Additional reporting by Robert-Jan Bartunek in Brussels; editing by Andrew Roche)