MOSCOW • Russia warned Syrian Kurdish YPG forces yesterday that they face further armed conflict with Turkey if they fail to comply with a Russian-Turkish accord calling for their withdrawal from the entire length of Syria's north-eastern border with Turkey.

Moscow's warning came shortly before a column of Russian military police arrived in the city of Kobani in northern Syria to facilitate the withdrawal of Kurdish YPG forces and their weapons 30km from the Syrian-Turkish border, under the deal struck by Russian President Vladimir Putin and his Turkish counterpart Recep Tayyip Erdogan after six hours of talks on Tuesday.

US President Donald Trump yesterday hailed the deal a success.

"Big success on the Turkey/Syria Border. Safe Zone created! Ceasefire has held and combat missions have ended," he tweeted.

"Kurds are safe and have worked very nicely with us. Captured ISIS prisoners secured."

A complete pullout of the YPG would mark a victory for Mr Erdogan, who launched a cross-border offensive on Oct 9 to drive the Kurdish militia from the border and create a "safe zone" for the return of Syrian refugees. The accord, which expands on a US-brokered deal last week, also underlines Mr Putin's dominant influence in Syria and seals the return of his ally President Bashar al-Assad's forces to north-east Syria for the first time in years, by endorsing the deployment of Syrian border guards yesterday. Russian and Turkish forces will later jointly start to patrol a 10km strip of land in north-east Syria where US troops had been deployed for years with their Kurdish allies.

Kurdish militia commanders have yet to respond to the deal reached in Russia's Black Sea resort of Sochi. It was not immediately clear how their withdrawal could be enforced.

A joint Turkish-Russian statement issued by Mr Putin and Mr Erdogan said they would establish a "joint monitoring and verification mechanism" to oversee implementation of the agreement.

The Kurdish-led Syrian Democratic Forces were Washington's main allies in the fight to dismantle the Islamic State in Iraq and Syria's self-declared caliphate in Syria.

In a further sign of growing ties between Ankara and Moscow, which has alarmed the US, the head of Russia's defence sales agency was quoted by the Interfax news agency yesterday as saying Moscow could deliver more S-400 missile defence systems to Turkey.

Turkey, a North Atlantic Treaty Organisation (Nato) member, has already been frozen out of a programme to buy and produce F-35 jets and faces possible US sanctions for buying the S-400 systems, which Washington says are incompatible with Nato's defences and threaten the F-35 if operated near the stealth fighter.

Turkey's Defence Ministry said the US had told Ankara the YPG had completed its withdrawal from the area of Turkey's military offensive. There was no need to initiate another operation outside the current area of operation, the ministry said, effectively ending a military offensive that began two weeks ago and drew global criticism.

Turkish sources said Ankara was re-evaluating a plan to set up 12 observation posts in north-eastern Syria in the wake of the deal.

REUTERS, AGENCE FRANCE-PRESSE