European Union governments have rejected Franco-British efforts to lift an EU arms embargo to allow weapons supplies to Syrian rebels, saying this could prompt an arms race and worsen regional instability.
France and Britain found little support for their proposal at an EU summit in Brussels, diplomats said, but EU foreign ministers will consider the issue again next week.
"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, Herman Van Rompuy, EU president, said at the close of a two-day summit in the Belgian capital on Friday.
On the second anniversary of the Syrian uprising, there was little appetite from some Europeans for arming the rebels, fearful that a flood of weapons into the country would only escalate the conflict.
German Chancellor Angela Merkel, whose country is traditionally wary 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."
'Political solutions failed'
After David Cameron, UK prime minister, this week called for an EU arms embargo to be lifted, 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," the French president said.
"We cannot allow a people to be massacred by a regime that for now does not want a political transition," he said.
Like Britain, France warned it was ready to break ranks with European partners to supply weapons to the rebels.
France 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," Cameron said.
"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.
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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 said in Brussels.
An EU diplomat said many countries were likely to fall in quietly behind Germany and refuse to lift the ban.
Speaking after the closing of the summit, Hollande suggested that France and UK 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."