French authorities will analyse samples brought back from Syria by two journalists after they reported the Syrian army was using chemical weapons against rebel forces, a top official said Tuesday.

There have been mounting reports of the use of chemical arms in Syria, where a bloody conflict has raged for over two years and claimed more than 94,000 lives amid reports of widespread rights violations.

A top French government official, who wished to remain anonymous, said Tuesday samples had been handed over to authorities by the journalists, without saying what the samples were from. "We have agreed to analyse them," he said.

The official added that, like the United States and Britain, France had already analysed its own samples and concluded that there were "clues but no formal evidence" of the use of chemical arms in Syria.

The two reporters from French newspaper Le Monde said they had "witnessed over several consecutive days" the use of explosive chemical arms and their effects on rebel fighters in the outskirts of Damascus.

Photographer Laurent Van der Stockt reported that on April 13 he saw fighters "suffocating and vomiting" in the village of Jobar outside the Syrian capital after an apparent attack using chemical weapons.

The journalists said they had gathered witness accounts of the use of chemical weapons in a large area around Damascus.

One doctor in a rebel-held area told the newspaper that the weapons caused breathing difficulties, headaches and nausea, and could cause death if victims
were not treated.

"The gases are used on the front on an ad hoc basis, avoiding widespread use that would easily provide irrefutable evidence," reporter Jean-Philippe Remy wrote.

French Foreign Minister Laurent Fabius said Monday there were indications of "localised use" of chemical arms in Syria, and the United Nations has called on Damascus to let in UN investigators.

Fabius hosted talks in Paris on Monday with Russian Foreign Minister Sergei Lavrov and US Secretary of State John Kerry.

Speaking after talks in a Paris hotel  , Lavrov said ensuring the success of the proposed peace conference was "not an easy task, it's a very tall order."

EU lifts arms embargo on rebels

A breakthrough was made on Monday in Brussels however where after fraught nine hour discussions EU ministers agreed to lift the embargo on arming Syrian rebels.

The move to lift of the embargo, announced by British Foreign Secretary William Hague was supported by Britain and France but most other EU nations opposed the move.

The talks had been "difficult," agreed British Foreign Secretary William Hague, though "the discussion was constructive".

Announcing the agreement after more than 12 hours of tough talks, Hague said the EU would maintain the remainder of a far-reaching package of sanctions against the Assad regime that are set to expire Friday at midnight.