Idlib is home to some three million people - about half of them displaced by fighting in other parts of the country during the war, now in its eighth year, according to the UN.
U.N. Special Envoy Staffan de Mistura began two days of talks in Geneva on Monday with senior officials from Russia, Iran and Turkey on forming a Constitutional Committee in Syria, but which were expected to be overshadowed by the Idlib crisis.
He also blamed terrorists for forcing the government to move on Idlib, a claim rejected by the U.S. and other nations, which argue that Russian Federation and the Assad regime are using that label to justify the military offensive.
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The situation in Syria is escalating.
The U.S. military said the main targets of the strikes were two storage facilities, one that produced sarin, and another was part of a command post, which were located west of the city of Homs.
The US ambassador, Nikki Haley, said Syrian forces, backed by Russian Federation and Iran, had already launched 100 airstrikes on Idlib this month and that their sole aim was "a bloody military conquest of Idlib".
In turn, Russia's UN Envoy Vasily Nebenzya told the UNSC that foreign-backed Idlib terrorists should not be shielded and allowed to hold civilians hostage. "The world will hold them responsible", she added.
Nebenzya emphasized that the de-escalation zones in Syria were created as "temporary entities", not permanent ones.
"Sooner or later, they were to be replaced, first by local truces".
"The Turkish border is sealed, the Turks have kept that border quite tightly shut for the past few years, so al-Assad's opponents don't have anywhere to run to", she said.
Nebenzya dismissed plans by the Syrian government to conduct a gas attack, saying that there was "irrefutable proof" showing that the militants were planning such an assault. "Turkey expects all parties to make constructive contributions and agree on a political solution on Syria", he said. "The consequences of inaction are immense" Erdogan said.
Turkish security sources on the ground in Idlib told MEE that they had visited areas where members of HTS, other fighters and civilians were all living in the same building and all carrying weapons.
"We've tried to convey the message in recent days that if there's a third use of chemical weapons, the response will be much stronger", Bolton said after a policy speech in Washington.
When asked what the US has done to prevent their use, Mattis referred to US, UK and French strikes on Syria after a chemical weapons attack in April. "It's an anti-terrorist operation".
The talks led by Staffan de Mistura started and ended with little or no comment to reporters at the United Nations offices in Geneva, and offered a sideshow to the concerns about a looming battle for the northern province - the last remaining rebel stronghold in Syria after 7½ years of war and now home to some 3 million civilians.
"The so-called peaceful co-existence with terrorists is simply impossible".
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".