Syrian state television showed a convoy of pro-government fighters entering the Kurdish Afrin region in Syrian Kurdistan (Rojava) on Tuesday to help fend off a Turkish assault.

The fighters wearing camouflage fatigues waved weapons and Syrian flags from their vehicles as they crossed through a checkpoint that bore the insignia of a Kurdish security force.

“One Syria, one Syria!” some of them chante

“We have come to tell our people in Afrin that we are one,” said a fighter interviewed on state television, referring to the government stance that Syria must remain one country and internal partitions caused by the war must be eradicated.

State news agency SANA accused Turkish forces of shelling territory near the crossing where the “popular forces” entered Afrin.

Earlier on Tuesday, Turkish President Tayyip Erdogan said Russia had stepped in to block a deployment of pro-government forces in Afrin, where Ankara is seeking to destroy the Kurdish YPG militia.

Erdogan later said in a phone call with Russian President Vladimir Putin that Damascus would face consequences if it struck a deal with the YPG and said the Afrin operation would continue, CNN Turk reported.

On Sunday, a Kurdish political official said Damascus had agreed to send Syrian troops into Afrin to help fend off the month-old offensive by Turkey and allied Syrian insurgents.

The Syrian government and the YPG have mostly avoided direct conflict during the war, but they espouse very different visions for Syria’s future. Each controls more ground than any other side in the conflict.

Turkey began its Afrin operation with allied Syrian fighters, seen as mercenary warriors for Turkey, last month against the YPG, which Ankara sees as a threat along its border with links to the Kurdish PKK insurgency at home.

Turkey is using YPG as pretext to invade the Syrian Kurdish region in order not allow Kurds to establish an autonomous region in Syrian Kurdistan, analysts say.

U.S. regards the Democratic Union Party (PYD) and its powerful military wing YPG/YPJ, as key ally against Islamic State IS and the most effective fighting force against IS in Syria and has provided them with arms, air support as well as the military advisers. The YPG has seized swathes of Syria from IS.