Government forces Thursday seized large parts of the key highway town of Saraqeb as they pushed an offensive in the last rebel enclave in northwestern Syria, a war monitor said.

Weeks of intensive aerial bombardment and a bruising ground offensive have emptied entire towns in the Idlib region and sent hundreds of thousands fleeing their homes.

As Russia-backed regime forces chipped away at the jihadist-dominated region, 23 Syrian and foreign fighters were killed in pre-dawn Israeli strikes on targets south of Damascus where the Jewish state says arch foe Iran has a presence.

The battle for Saraqeb, which sits at the junction of two major highways coveted by the regime, came as Turkey sent reinforcements north of the town overnight, a day after Ankara warned pro-Damascus forces to back off.

After breaking into Saraqeb on Wednesday, Syrian regime forces on Thursday seized large sectors of the town after a day of heavy battles against rebels and jihadists, the Syrian Observatory for Human Rights said.

The Britain-based war monitor said the forces pushed back a “counter-offensive” by the opposition fighters in Saraqeb, a town of 110,000 residents now almost deserted following months of bombardment.

Syria’s state news agency SANA confirmed the report saying government troops were carrying out “mopping up” operations as well as “dismantling mines and explosives” planted there by the rebels and jihadists.

The UN Security Council was due to meet on Thursday in New York at an emergency session following clashes this week between the Syrian and Turkish militaries. The UN envoy for Syria, Geir Pedersen, was to report on the situation in Idlib.

Tension between Ankara and Damascus mounted after Turkish and regime forces on Monday exchanged deadly fire in a rare escalation that killed more than 20 people on the two sides.

The uptick in bombardment of the Idlib region of some three million people has killed more than 300 civilians since mid-December, including 17 on Thursday, the Observatory said.

Ten of those killed on Thursday perished in a Russian air strike on the eastern outskirts of Idlib city, the monitor said.

The United Nations and aid groups have called for an immediate end to the violence, which has pushed around 586,000 people from their homes in two months.

Erdogan warning

Turkey, which has troops deployed in northwestern Syria where it backs the rebels, has repeatedly called on Damascus  and its ally Russia to stop the offensive against Idlib.

On Wednesday Turkish President Recep Tayyip Erdogan again demanded an end to the Syrian push into Idlib.

“If the regime does not pull back, Turkey will be obliged to take matters into its own hands,” Erdogan told a meeting of ruling party lawmakers in Ankara, giving Syria until the end of the month to comply.

Early Thursday, Turkish troops arrived in the area of Taftanaz, some 16 kilometres (10 miles) north of Saraqeb, it said.

The Syrian army in a statement accused the Turks of obstructing its advance and “impeding it from completely stamping out the organised terrorism besieging civilians in Idlib province”.

The Observatory also reported clashes Thursday north, west and south of Saraqeb, backed by Turkish artillery fire. Ankara did not confirm its involvement.

Under a 2018 deal with Moscow, Turkey has 12 observation posts in Idlib aimed at preventing a regime offensive.

The Damascus regime controls more than 70 per cent of Syrian territory and has repeatedly vowed to reclaim the entire country, including Idlib. It has taken a string of villages and towns in recent weeks.

The region, and nearby areas of Aleppo and Latakia provinces, are dominated by the Hayat Tahrir al-Sham (HTS) jihadist group, led by members of the country’s former Al-Qaeda franchise.

Israeli air strikes

Pre-dawn air strikes by Israel’s military on Thursday killed 23 Syrian and foreign fighters.

Three Iranians and seven Tehran-backed foreign fighters were killed near Kisweh south of the capital, according to the Observatory.

Eight Syrian air defence personnel meanwhile lost their lives in Mezzeh and Jisr Baghdad, west of the capital, the Britain-based war monitor said.

Five Syrian members of a pro-Iran group were killed in the Ezra area in the southern province of Daraa.

A Syrian army source quoted by state news agency SANA said air defences responded to two waves of Israeli strikes after midnight.

An Israeli army spokesman declined to comment on the strikes when contacted by AFP but the Jewish state has carried out repeated strikes in Syria since the civil war erupted, mainly targeting government forces and their Iranian and Hezbollah allies.

Syria’s war has killed more than 380,000 people and displaced millions since it started in 2011 with the brutal repression of protests against President Bashar al-Assad.