The French ambassador to the UN on Tuesday called for unity and action at the Security Council after a discussion on a report establishing responsibility for chemical attacks in Syria.

The Assad regime and the Daesh terrorist group are responsible for three chemical weapons attacks in the war-torn country, according to the Joint Investigative Mechanism (JIM) report.

"If there is one thing that must unite the Security Council, it is the fight against the proliferation and use of weapons of mass destruction," ambassador Francois Delattre told the Council.

"Beyond the situation in Syria, what is at stake here is the future of the non-proliferation regime, which is a backbone of international peace and security," Delattre said. "What is also at stake is the credibility of the Security Council and of the UN system. Each of us will be accountable for it."

Delattre urged Council members to impose sanctions on those responsible and extend the JIM's mandate for another year while granting the group enhanced means to continue its investigations.

Virginia Gamba, head of the JIM, told reporters that regime forces carried out two chemical attacks -- one in Talmenes on April 21, 2014, and the other in Sarmin on March 16, 2015 -- and Daesh was responsible for one in Marea on Aug. 21, 2015.

Gamba said the group continued to investigate three other cases where it was drawing closer to apportioning responsibility.

She said the JIM was "acutely aware of the ongoing use of chemicals as weapons" in Syria, and noted "with great concern that there is a diversification of both the type of chemicals used and the actors involved", calling for accountability.

Vitaly Churkin, the UN ambassador of the Russian Federation, a long-term ally and sponsor of Assad, told reporters Tuesday that while there was a "smoking gun" on chemical weapons use in Syria, "there are no fingerprints on the gun."

He said he did not believe the report was enough to impose sanctions on Syria.

Churkin said however that Russia was ready to encourage the Syrian regime to continue to cooperate with the JIM, assuring that his stances was not aimed at undercutting the effectiveness and the usefulness of the group.

Reports of chemical attacks on civilian populations and opposition fighters have continued to come out of Syria since an attack in August 2013 killed more than 1,400 victims in East Ghouta near Damascus.

The Syrian Network for Human Rights said it documented 139 chemical attacks in Syria since September 2013 when the Security Council issued resolution 2118 for the dismantling of Syria's chemical weapons arsenal.

"Some 136 attacks were carried out by the Syrian regime," the London-based group said.

It added that Daesh had also carried out three chemical attacks in Syria since 2013. According to the rights group, approximately 88 victims had been killed in chemical attacks in Syria since 2013, including 45 opposition fighters and 36 civilians.

The group registered the highest number of chemical attacks in northern Idlib province, Rif Dimashq province and central Hama province.

In August 2012, President Barack Obama said the use of chemical weapons would be a "red line" for the U.S., indicating Washington would take military action against perpetrators of such an attack.

A year later, the U.S. changed course, choosing instead to negotiate with the Syrian government for the total elimination of its chemical arsenal, which was achieved in 2014.

Anadolu Agency, in 2014 and last week, published images of the Ghouta attack to raise awareness on the issue.

Anadolu Agency's new video of the attack, depicting dead bodies of the women and children at the scene, also shows doctors trying to revive victims affected by the chemical gas attack.

Chemical attacks have been one aspect of an inhumane warfare spanning five years that has decimated Syria.

More than a quarter of a million people have been killed and more than 10 million displaced across the war-battered country, according to the UN, since the regime of Assad regime responded to peaceful protests in 2011 with military force, pushing the country into a vicious downward spiral of violence.

The Syrian Center for Policy Research puts the death toll from the six-year conflict at more than 470,000 victims.