BEIRUT – The US-backed Syrian Democratic Forces will work with Syrian government troops to fend off any Turkish invasion in the north, according to the SDF commander, who also stated that Damascus should deploy its air defence systems to counter Turkish planes.

Ankara has promised a major onslaught against the SDF, a Kurdish-led alliance led by the Kurdish People’s Protection Units, which controls large swaths of northern Syria (YPG).

The fresh threats have emphasised the complicated web of ties in northern Syria: while Turkey regards the YPG as a terrorist organisation, Syrian Kurdish forces are backed by the US and have worked with the Syrian government and its ally Russia.

Mazloum Abdi, the SDF’s commander, said on Sunday that his forces were “open” to collaborating with Syrian troops in the fight against Turkey, but that no extra forces were required.

“The most important thing the Syrian army can do to defend Syrian territory is utilise air defence systems against Turkish jets,” he said in a telephone interview from an unidentified location in northern Syria.

Syria views Turkey as an occupying force in its north, and Damascus’ foreign ministry declared last month that any additional Turkish invasions would be considered “war crimes and crimes against humanity.”

In fighting with Syrian President Bashar al-army Assad’s and the SDF, Turkey has helped rebel groups. It has employed bombers and, increasingly, drones to attack SDF-held territory, where Syrian Kurdish authorities have established a separate government structure from Damascus.

More military coordination with Damascus, according to Abdi, would not jeopardise the semi-autonomous authority.

“Our top goal is defending Syrian land, and no one should consider exploiting the situation to gain ground,” he said.

Turkish President Tayyip Erdogan has promised to retake the SDF-held cities of Tal Rifaat and Manbij in Syria’s northern Aleppo region, which is largely controlled by Syrian government forces.

In prior years, Turkish-backed raids drove the SDF out of Afrin, a northwestern enclave, and a succession of border towns to the east.

Abdi said a new offensive would displac 1 million people and lead to “wider” battle zones, but he wouldn’t specify whether the SDF would retaliate with attacks on Turkish soil.

He cautioned that it might lead to a rebirth of the extremist Islamic State group, which the SDF drove out of large swaths of northern and eastern Syria with the help of US air power.

Redeploying SDF fighters to combat Turkey might leave security holes in camps and prisons where IS members and IS-affiliated families are imprisoned.

“We can’t fight on two fronts at the same time,” Abdi remarked.

He expressed hope that a meeting between Russia’s and Turkey’s foreign ministries will lead to a de-escalation, but added that any negotiated settlement must involve an end to Turkish drone assaults in northern Syria.

He stated, “This would be one of our major needs.”