"The Commission concludes that, on these two occasions, government forces and/or affiliated militias committed the war crimes of using prohibited weapons and launching indiscriminate attacks in civilian-populated areas in eastern Ghouta", it said.
"There need to be ways of dealing with this problem that doesn't turn the next few months in Idlib into the worst humanitarian catastrophe with the biggest loss of life in the 21st century", Mark Lowcock told reporters in Geneva.
He added that Russian Federation and Iran were also responsible for stopping a humanitarian disaster in Idlib, and said the worldwide community had to "throw its weight behind a political solution".
"There might be another refugee flow but we plan not to open our borders and settle the refugees in the camps prepared for them on the Syrian side of the border", Volkan Bozkir, the head of the Turkish parliament's foreign affairs committee and a former government minister, told the Cumhuriyet newspaper.
Britain and France backed the call for a ceasefire, recalling that these had been agreed under arrangements for a "de-escalation zone" in Idlib that were overseen by Russia, Iran and Turkey.
"It is absolutely essential to avoid a full-scale battle in Idlib", Guterres told reporters at United Nations headquarters.
"This would unleash a humanitarian nightmare unlike any seen in the blood-soaked Syrian conflict".
The province and its surrounding areas are the last major enclave held by rebels opposed to Syrian President Bashar al-Assad.
Turkey, which has sent troops to Idlib and supports some of the armed groups, called for an immediate ceasefire and urged the global community "to vocally and actively support our efforts to this end". Soli Ozel, an global relations expert with Istanbul's Kadir Has University, asked how Turkey could "have a war with the Syrian regime, if the Syrian regime is being supported by the Russians to the bitter end, and the Russians control the airspace?"
Turkey, which has sent troops to Idlib and supports some of the armed opposition, called for "an immediate ceasefire" and urged "the global community to vocally and actively support our efforts to this end".
The three countries a year ago set up the Astana process, a negotiating track to end Syria´s war that has largely eclipsed the UN-led peace process.
Turkish Foreign Minister Mevlut Cavusoglu on Tuesday also called on worldwide allies to work together in Syria's Idlib with efforts to prevent civilian casualties.
"What we propose is very clear. That's why it is necessary to eliminate them, as a phenomenon".
Cardi B's Stylist Comes To Her Defense Following Nicki Minaj Brawl
According to TMZ Cardi confronted Nicki at the party and threw her shoe at her when she could not physically reach her. I would never ridicule anyone's child. "These lies are ridiculous".
"What Ankara said about Turkey's operations into Syria is to keep the PKK away from the Turkish borders", he said, adding, "The unsaid objective is to keep Assad far from Turkey's borders".
In the article, Erdogan said "All members of the global community must understand their responsibilities as the assault on Idlib looms".
But while Erdogan had also called for a truce, Putin said this would be pointless as it would not involve the Islamist militant groups that Russian Federation deems terrorists, and Rouhani said Syria must regain control over all its territory.
"A regime assault [in Idlib] would also create serious humanitarian and security risks for Turkey, the rest of Europe and beyond", he added.
USA ambassador Nikki Haley accused the regime's main backers of escalating the violence in Idlib province and using terrorist tactics.
She said the Astana process, designed by Moscow to negotiate peace in Syria, was a failure.
United Nations agencies and relief organisations have warned repeatedly that any major assault could spark one of the worst humanitarian disasters of Syria's war. While investigating reports of the use of such weapons in Syria, the OPCW's mission was to determine if they had been used, but not who was responsible.
The Turkish army has also deployed in the last week more troops and heavy weaponary to 12 positions in the Idlib region that observe a "de-escalation zone" agreed with Iran and Russian Federation.
"It is a disgusting tactic of terrorists, not professional soldiers", Halley said. "If Assad, Russia, and Iran continue down the path they are on, the consequences will be dire".
"Some even said that they are preparing to die as Idlib is the last safe place for many of them".
Russian Federation responded and insisted that the planned assault on Idlib is a "counterterrorism operation" and that measures will be taken to spare civilians.
The UN has said around 800,000 people could be displaced if a full-scale attack is carried out.
"President Bashar al-Assad of Syria must not recklessly attack Idlib Province", Trump wrote September 3 on Twitter.
About half of those displaced so far have moved to camps, while others went to informal settlements, stayed with families or rented housing, OCHA spokesman David Swanson said on Monday. Unlike many other news organizations, we have not put up a paywall.