France said on Tuesday the conflict in Syria had reached a "turning point" after the fall of the city of Qusair to President Bashar al-Assad's forces, raising the question of whether to arm Syrian rebels.
The battlefield tilted against the rebels in Syria's civil war last week as Lebanese Hezbollah militants helped Assad's forces to retake the strategic town.
The weakening of Syria's rebels after Qusair and other losses made it more difficult to bring them to the negotiating table with representatives from Assad's government, said France's Foreign Ministry spokesman, Philippe Lalliot.
"With the fall of Qusair, we are seeing a dramatic development," he said. "It's even more worrying given that Aleppo is being announced as the next target of the regime and its allies ... We are at a turning point in the Syrian war."
France is among Western countries including the United States and Britain that say Assad has lost his legitimacy as Syria's ruler, although they have shied away from arming the rebels for fear of bringing Islamist Jihadists to power.
Lalliot said a French official would be talking at the weekend to Salim Idris, head of the Free Syrian Army, in Turkey. The official had also started talks with the United States, Saudi Arabia, Turkey and others on how to strengthen the rebels.
"There are consequences to be drawn from what happened in Qusair and what's happening in Aleppo. The first consequence is to strengthen the ties with the coalition, and the question we're asked is whether to go one step further and deliver weapons," Lalliot said.
The lifting of a European Union embargo on arms deliveries to Syria, and rapid changes on the battlefield, meant that "talks and thinking" were now needed on the issue, he added.
"We cannot leave the opposition in the situation in which it finds itself."
The United States and Russia are trying to bring Assad's government and his opponents together, but are still at odds on several issues before the talks can begin.
"The serious weakening of one of the parties does not help efforts to hold the Geneva conference," said Lalliot. "In order for both sides to negotiate, one side must not be too weak and the other too strong."