Pressed by the two major EU powers to help tip the balance in the conflict by arming the ill-equipped rebels fighting President Bashar al-Assad, leaders of the 27-nation bloc agreed to discuss the issue again next week, but there was little sign of a deal in the offing.
"We agreed to task our foreign ministers to assess the situation as a matter of priority" at talks in Dublin on March 22 and 23, EU President Herman Van Rompuy said at the close of a two-day summit.
As the bloody conflict entered its third year, London and Paris said there was no sign of Assad relenting on the political front as he continued to receive arms from Russia and elsewhere.
But there was little appetite from some Europeans for arming the rebels, fearful that a flood of weapons into Syria would only escalate the conflict.
"It is unlikely there will be an agreement to lift the arms embargo given very principled opposition from some nations, such as Germany," Jan Techau, head of the Carnegie think-tank, told AFP.
German Chancellor Angela Merkel, whose country is traditionally shy of conflict, said "I haven't made up my mind yet", but added that "we have a series of reservations because one has to ask whether or not one is fanning the flames of the conflict."
"It is an extremely difficult situation," she added after the summit. "It must be considered very very carefully."
After British Prime Minister David Cameron this week called for an EU arms embargo to be lifted, France's President Francois Hollande unexpectedly turned the spotlight on the issue on arriving in Brussels, saying: "We want Europeans to lift the arms embargo."
"Political solutions have now failed," he said. "We cannot allow a people to be massacred by a regime that for now does not want a political transition," Hollande said.
Like Britain, France warned it was ready to break ranks with European partners to supply weapons to the rebels. Paris was ready to "take its responsibilities" if other EU nations were unwilling to lift the embargo, Hollande said.
"Of course people want a political solution," said Cameron. "We are more likely to see political progress if people can see the Syrian opposition as a credible and strengthening force."
The EU embargo on supplying arms to Syria, whether to the regime or rebels, is part of a package of sanctions that was extended on February 28 for three months by EU foreign ministers, though such sanctions are always reviewed in case events change.
At the February talks ministers agreed under pressure from Britain, France and Italy to ease the arms ban to enable any EU state to provide non-lethal aid or training to the insurgents.
Britain quickly pledged armoured vehicles and protective clothing for the opposition.
But a number of EU countries have been sceptical about going further and dropping the arms ban.
"We are against the end of the arms embargo. We think the delivery of arms does not contribute to a possible solution," Austrian Chancellor Werner Faymann told reporters in Brussels.
An EU diplomat said many countries were likely to fall in quietly behind Germany and refuse to lift the ban.
Carnegie think-tank analyst Techau said the dispute would further undermine EU efforts to speak with one voice on the world scene.
"It will make the EU look exactly as it is -- that is, not unified -- dealing another blow to the bid to build a common foreign and defence policy."
Techau said Britain and France were likely to press ahead on their own if necessary.
Speaking at a news conference closing the summit, Hollande suggested that Paris and London were determined to act.
"Inaction is the greatest risk," he said. "It is preferable to control weapons than just allow them to circulate freely as is the case today."
