Last week the French ambassador, whose country also vowed to strike Syria if what it deems credible chemical allegations emerge, said during a U.N. Security Council meeting on Idlib: "Syria is once again at the edge of an abyss".
He urged the West, including the USA, to join hands in stopping a possible attack on Idlib.
But his Defence Minister Hulusi Akar says Turkey remains determined to halt the weeks-long air strikes on Idlib and forestall a ground offensive, while officials warn that Turkey would respond if its forces inside Idlib come under fire.
Two children were killed in heavy barrel bomb attacks on a village in Idlib's south Sunday, a day after 10 civilians died in shelling across the rebel zone, the Syrian Observatory for Human Rights monitoring group said.
Turkey, which has sent troops to Idlib and supports some of the armed groups, called for an immediate ceasefire and urged the worldwide community "to vocally and actively support our efforts to this end".
Russian warplanes are already bombing rebels across Idlib, a bombardment predicted to intensify ahead of the widely expected offensive.
The council will meet at Russia´s request at 11:00 am (1500 GMT) to hear the briefing as Syrian forces, backed by Russian Federation and Iran, are preparing for an all-out military assault on the rebel-held province.
In an article posted Monday in The Wall Street Journal, Erdogan warned, "The consequences of inaction are enormous", and "a regime assault would also create serious humanitarian and security risks for Turkey, the rest of Europe and beyond".
But he said Russia's President Vladimir Putin and Turkish President Tayyip Erdogan were working hard to find a solution.
United States ambassador Nikki Haley accused the regime's main backers of escalating the violence in Idlib province and using terrorist tactics.
Haley warned Assad and his allies that any assault on Idlib would be considered "reckless" by the United States and "the consequences will be dire". 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 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.
She also said that "Russia has the power to stop the catastrophe looming in Idlib".
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.
The northwestern province and adjacent areas form the largest chunk of territory still held by the rebels, who have been worn down by a succession of defeats in other parts of the country.
"President Bashar al-Assad of Syria must not recklessly attack Idlib Province".
"We're deeply concerned about this recent escalation of violence, which has resulted in the displacement of over 30,000 in the area".
There are also tens of thousands of rebels from Turkey-backed Free Syrian Army groups as well as millions of civilians - many already displaced from other parts of Syria.
The security source said Turkey was preparing more camps, but said discussions were still continuing about the scale of the aid operation inside Syria.
He acknowledged that there were many rebels and fighters from "terrorist" groups in the province, but stressed that "there are 100 civilians, a lot of them women and children, for every fighter in Idlib".