Kurdish fighters battled to defend a key Syrian border town from Turkish-backed forces in a flare-up of violence Tuesday as US President Donald Trump sent his vice president and top diplomat to Ankara to demand a ceasefire.

The ethnically divided Kurdish-held border town of Ras al-Ain is one of the key targets of Turkey's nearly week-old invasion and has ome under heavy bombardment
The ethnically divided Kurdish-held border town of Ras al-Ain is one of the key targets of Turkey's nearly week-old invasion and has ome under heavy bombardment AFP / Ozan KOSE

Russia, already the key foreign power in Syria, stepped into the void caused by Trump's withdrawal of US troops by deploying patrols to prevent clashes between Syrian and Turkish forces.

Map of northeast Syria locating Tal Abyad and Ras al-Ain and areas where Syrian forces are deployed, as well as the M4 highway
Map of northeast Syria locating Tal Abyad and Ras al-Ain and areas where Syrian forces are deployed, as well as the M4 highway AFP /

As Ankara tries to crush Kurdish forces in northeastern Syria it links to separatists at home, artillery fire by pro-Turkey rebels killed two Syrian regime soldiers near the town of Ain Issa, the Syrian Observatory for Human Rights war monitor said.

President Bashar al-Assad's troops have returned to key northern areas for the first time in years in a deal with the Kurds, seeking protection after Trump ordered the withdrawal of some 1,000 US troops.

Syrian Arab civilians flash the victory sign as Turkish tanks and armoured personnel carriers gather on the outskirts of the flashpoint Syrian city of Manbij
Syrian Arab civilians flash the victory sign as Turkish tanks and armoured personnel carriers gather on the outskirts of the flashpoint Syrian city of Manbij AFP / Aaref WATAD

Trump, facing mounting criticism in Washington on Syria as well as an unrelated impeachment inquiry, has hit back at Turkish President Recep Tayyip Erdogan, slapping sanctions on three cabinet officials and raising tariffs on the country's steel.

Kurdish authorities have warned repeatedly that they cannot tackle the Turkish invasion and guard tens of thousands of jihadist pironers and their familes at the same time
Kurdish authorities have warned repeatedly that they cannot tackle the Turkish invasion and guard tens of thousands of jihadist pironers and their familes at the same time AFP / DELIL SOULEIMAN

Vice President Mike Pence said he would meet with Erdogan on Thursday and "voice the United States' commitment to reach an immediate ceasefire and the conditions for a negotiated settlement", his office said in a statement.

Syrian former rebels, who have been Turkey's main ground partners in its cross-border offensive, have made advances elsewhere along a 120 kilometre (75 mile) front but have met fierce Kurdish resistance in Ras al-Ain
Syrian former rebels, who have been Turkey's main ground partners in its cross-border offensive, have made advances elsewhere along a 120 kilometre (75 mile) front but have met fierce Kurdish resistance in Ras al-Ain AFP / Nazeer Al-khatib

He reiterated that Trump will pursue "punishing economic sanctions" until a resolution is reached.

In a sign of US determination, Pence will lead a high-powered team that includes Secretary of State Mike Pompeo, Trump said.

Turkish forces advance north of the Syrian city of Manbij as part of a sweeping offensive against the Kurds
Turkish forces advance north of the Syrian city of Manbij as part of a sweeping offensive against the Kurds AFP / Aref TAMMAWI

But Erdogan was defiant ahead of the visit.

Tens of thousands of Syrian civilians have fled the fighting
Tens of thousands of Syrian civilians have fled the fighting AFP / Delil SOULEIMAN

"They tell us 'to declare a ceasefire'. We can never declare a ceasefire," Erdogan told journalists on a flight back from Azerbaijan, in comments published by the Hurriyet daily.

AFP Videographics / Fred Garet, Emmanuelle Bailllon

European powers -- who are particularly spooked by the prospect that Islamic State group fighters jailed by the Kurds will go free -- have taken an increasingly tough tone with Turkey.

Britain and Spain became the latest powers to suspend military exports to Turkey. Canada made a similar move.

Syrian government soldiers have deployed on the outskirts of the city of Manbij
Syrian government soldiers have deployed on the outskirts of the city of Manbij AFP / -

Kurds try to defend border

A day after regime forces entered the key city of Manbij, the Kurdish-led Syrian Democratic Forces (SDF) are mounting a desperate defense to the east of the border town of Ras al-Ain, using tunnels, berms and trenches.

A missile fired by Turkish forces towards the Syrian town of Ras al-Ain, from the Turkish side of the border
A missile fired by Turkish forces towards the Syrian town of Ras al-Ain, from the Turkish side of the border AFP / Ozan KOSE

An AFP correspondent in the area said clashes around the town continued Tuesday, despite Ankara's repeated claims it had captured the area.

Map locating control of territory in northeastern Syria after Turkey launched an offensive against Kurdish forces, includes Ankara's planned "buffer zone" and towns with presence of Syrian regime forces.
Map locating control of territory in northeastern Syria after Turkey launched an offensive against Kurdish forces, includes Ankara's planned "buffer zone" and towns with presence of Syrian regime forces. AFP /

The Syrian Observatory for Human Rights said Kurdish fighters had launched "a large counterattack against Turkish forces and their Syrian proxies near Ras al-Ain", later reporting "fierce combat" in the west of town as well as in Tal Abyad.

Since launching their assault on October 9, Turkish-backed forces have secured more than 100 kilometres (60 miles) of border, but Ras al-Ain -- Siri Kani in Kurdish -- has held out.

The ethnically divided Kurdish-held border town of Ras al-Ain in Syria is one of the key targets of Turkey's invasion and has come under heavy bombardment
The ethnically divided Kurdish-held border town of Ras al-Ain in Syria is one of the key targets of Turkey's invasion and has come under heavy bombardment AFP / Ozan KOSE

Erdogan, who like Trump faces political difficulties at home, wants to create a buffer zone stretching 30 kilometres (20 miles) from the border into Syrian territory.

He wants to keep at bay the SDF as well as resettle some of the 3.6 million Syrian refugees now in Turkey.

"God willing, we will quickly secure the region stretching from Manbij to our border with Iraq," Erdogan said.

The offensive has killed dozens of civilians, mostly on the Kurdish side, and displaced at least 160,000 people.

Russia fills void

Russia said its military police were patrolling a zone separating regime troops and Turkish forces, in cooperation with Ankara.

Russia's special envoy on Syria, Alexander Lavrentyev, said Turkish and Syrian officials were in contact to avoid clashes which "would simply be unacceptable".

Russian Defence Minister Sergei Shoigu also discussed Syria in a phone call with his US counterpart Mark Esper, Moscow said.

With Trump's critics saying that he handed over US allies and stretches of Syria to Russia, the United States tried to play down Moscow's role.

"The number of Russians is very, very limited. But it only takes a few Russians with a big Russian flag to get everybody to pay attention," a senior administration official told reporters in Washington.

Jihadist breakouts

The Kurds lost 11,000 fighters as they helped Western powers crush IS.

European governments fear that the chaos could trigger mass breakouts by thousands of IS fighters, triggering a resurgence of the lethal group that has wreaked havoc through attacks in the West.

The Kurds have said hundreds of IS relatives have escaped.

An SDF official on Twitter Tuesday said more IS relatives had tried and failed to escape the overcrowded camped of Al-Hol in eastern Syria.

The US official, however, said that Washington was not aware of any "major" jihadist breakout, although between 50 and 150 women and children had fled.

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