UN Secretary General Antonio Guterres voiced deep concern Wednesday for the "growing risk" of a full-scale Syrian regime offensive in northwest province of Idlib.
"The Secretary-General urgently appeals to the Government of Syria and all parties to exercise restraint and to prioritize the protection of civilians," Guterres spokesman Stephane Dujarric said in a statement.
Guterres maintained "any use of chemical weapons is totally unacceptable."
He called on Turkey, Russia and Iran to "find a peaceful solution to the situation in Idlib, the last remaining de-escalation zone."
The countries are known as the "Astana guarantors" due to their role in peace talks the Kazakh capital to at end Syria's over seven-year conflict.
Located near the Turkish border, Idlib in May was designated a de-escalation zone where acts of aggression are expressly forbidden as part of the ongoing Astana process.
Guterres called "on all parties to take all necessary measures to safeguard civilian lives, allow freedom of movement, and protect civilian infrastructure, including medical and educational facilities, in accordance with international humanitarian law and human rights law."
Amid the UN chief's urgent plea, Russian Foreign Minister Sergey Lavrov said Wednesday the Russian and Turkish militaries are discussing "practical actions" against terrorists in Syria's Idlib.
"The political understanding fully exists between Moscow and Ankara; it is urgent to separate normal armed opposition from the bandits of al-Nusra Front and at the same time to prepare an operation against these terrorists, doing everything to minimize the risks to the civilian population," Lavrov said while referring to Idlib as "the last major hotbed of terrorists".
"How to translate this political agreement into the language of practical actions -- it has been discussed by the militaries of Russia and Turkey, who handle the situation on the ground," he said.
Lavrov said he expects the West to not obstruct the planned military operation against al-Nusra Front, which has been renamed to Hayat Tahrir al-Sham, in Idlib.
Syria has only just begun to emerge from a devastating conflict that began in early 2011, when the Bashar al-Assad regime cracked down on protesters with unexpected ferocity.
UN officials estimate hundreds of thousands of civilians have been killed in the conflict.
