France on Wednesday urged the international community to stop the progression of Syrian troops, backed by Hezbollah fighters and Iran, towards the strategic northern town of Aleppo.
After winning a strategic victory by retaking Qusayr, an important town near the border with Lebanon, Syrian troops are now focusing their attention on Aleppo as they continue to gain ground against the rebels.
"We must stop this progression before Aleppo. It is the next target of Hezbollah and of the Iranians," Foreign Minister Laurent Fabius said on France 2 television.
"We need to re-balance things because over the past few weeks the troops of Bashar al-Assad (Syrian leader) and especially Hezbollah and the Iranians, along with Russian arms, have gained considerable ground."
But he did not expand on how Syrian troops, buoyed by military support from its Shiite allies Hezbollah and Iran, should be stopped.
On Tuesday, France's foreign ministry warned that the nearly 27-month Syrian conflict, which is estimated to have killed at least 94,000 people, was at a "turning point."
"What should we do under these conditions to reinforce the opposition armed forces? We have had these discussions with our partners, with the Americans, the Saudis, the Turks, many others," said ministry spokesman Philippe Lalliot.
"We cannot leave the opposition in the current state."
The European Union, under pressure from London and Paris, last month failed to renew an arms embargo on Syria, leaving individual member states free from August 1 to supply weapons to the opposition, if they decide to do so.
Fabius said France had not yet decided what to do after the deadline.
"Bashar... used chemical weapons in an outrageous manner. We must stop him because, if there is no re-balancing on the ground, there will be no peace conference in Geneva as the opposition will refuse to come," he said.
The United States said it is evaluating information received from France which Paris has billed as proof that chemical weapons have been used in Syria.
The United States and Russia are meanwhile trying to organise a peace conference bringing together Assad's regime and the rebels in a bid to end the fighting.
Amid wrangling between opposition leaders and a fierce debate over who should attend, the date for the talks initially slated for May has now slipped back to July at the earliest.