With rebels defeated in most of Syria, such an offensive could prove to be the last big battle of the civil war.
United Nations investigators have already attributed several chemical attacks in Syria to government forces, including one attack using the nerve agent Sarin gas against the Idlib town of Khan Sheikhoun in April 2017. Syria-based rights group had accused Russian airstrikes of killing 1,207 civilians, 380 of them children, in the Aleppo offensive.
The Egyptian military said it will host the Americans for the second straight year for the "Bright Star" exercises starting September 8, and U.S. Central Command said Thursday that approximately 800 U.S. troops will be on hand.
"This is the condition set by Moscow to avert a broad offensive".
"The lives of 2.9 million people are at stake, and global mutually threatening messages and warnings and counter-warnings are taking place in the last few days".
"Turkey's relationship with HTS is a complicated one but may best be framed as cooperative animosity", said analyst Elizabeth Teoman, of the Institute for the Study of War.
Russian Deputy Foreign Minister Mikhail Bogdanov told Russian news agencies that Moscow is willing to discuss "the details, the general idea and what practical solutions there are". "Terrorists oppose such separation", Lavrov noted.
The U.S. State Department has said it will hold Moscow, an ally of Damascus, responsible if government forces use chemical weapons in the battle for Idlib.
Russian media reported this week that Moscow has been reinforcing its military set-up in the region and now has 10 warships and two submarines in Syrian waters.
"The special envoy's role is not to call for a humanitarian corridor, but to call on Russian Federation to stop the aggression".
He said a full-scale military operation in Idlib could lead to a "humanitarian catastrophe".
Concern is mounting meanwhile over the potential use of chemical weapons, and the Russian navy is building up its presence in the Mediterranean Sea.
"I am once again prepared. personally and physically to get involved myself.to ensure such a temporary corridor would be feasible and guaranteed for the people so that they can then return to their own places once this is over", Staffan de Mistura told reporters in Geneva. "We would be witnessing the most horrific tragedy to the largest number of civilians". They don't think any armed group in [Idlib] city is different than others, they consider them all terrorists.