On Wednesday, regime forces entered the strategically located city of Saraqib, northwest of Syria, hours after Turkish President Recep Tayyip Erdogan gave Damascus until the end of this month to withdraw its forces from the vicinity of observation points set up by Ankara in the region.

System forces began combing the city’s neighborhoods after hundreds of armed opposition fighters withdrew from them to a village north of it, according to the Syrian Observatory for Human Rights.

Al-Jazeera correspondent said that the Turkish observation points stationed in Jabal Aqil in the western countryside of Aleppo began shelling the regime forces attacking the city with Saraqeb area.

For his part, US special envoy on Syria, James Jeffrey, said on Wednesday that his country is "very concerned" about the escalation in Idlib, led by an attack by Syrian government forces and with the support of the Russians, and reiterated Moscow's demand to change its policies.

The Security Council is holding an emergency meeting on Thursday afternoon to discuss the developments in Idlib, while eight of the major international relief organizations in an urgent appeal warned of the repercussions of the situation and called for an immediate ceasefire, warning of a "humanitarian catastrophe" as hundreds of thousands of civilians fled the military operations.

Trapped displaced people
In a related context, relief groups and doctors said that the cold weather, disease, lack of shelter and medicine, pests threatening hundreds of thousands of civilians fleeing the raging fighting in the Syrian province of Idlib in one of the largest displacements during the war raging for nearly nine years.

The IDPs, whose numbers are growing daily, are besieging the advanced Syrian army forces that are keen to crush the last prominent stronghold of the opposition militants, and between the closed Turkish borders.

Some are forced to flee on foot, while others are forced to sleep in their cars, as Syrian and Russian aircraft bomb the highways heading north towards Turkey.

An official at the United Nations appealed to the world to provide emergency financial assistance to 800,000 people in northwestern Syria in the coming months.

For his part, Salim Toson, media advisor to the Turkish Humanitarian Relief Organization in Syria, said that the number of displaced people has increased in recent days as the Syrian government forces advanced to become eight kilometers from the city of Idlib.

"If the cold weather continues, there will be a possibility of the spread of epidemics as the flow of the displaced continues in large numbers," he added.

It is noteworthy that the progress of the regime forces came after a week of violent battles and shelling in the surrounding of the city, after its control last Wednesday of the city of Maarat al-Numan, the second largest city of Idlib governorate.

Since December, regime forces, with Russian support, have stepped up their campaign against and around areas in Idlib, which house more than three million people, half of whom are displaced from other provinces, and controlled by the Headquarters for the Liberation of Al-Sham and its allies, as well as less influential opposition factions.