Meanwhile, the town of Ras al-Ayn, scene of some of the fiercest fighting of the Turkish invasion, emerged as an immediate test for the five-day ceasefire agreed on by Washington and Ankara. Before the deal's announcement, Turkish-backed forces had encircled the town and were battling fierce resistance from Kurdish fighters inside. Smoke billows from a fire in Ras al-Ayn, Syria. Credit:AP A spokesman for the Kurdish-led fighters said on Friday they were not withdrawing from Ras al-Ayn because Turkish forces were still besieging and shelling it. Elsewhere along the border, calm seemed to prevail. Shelling hit in and around Ras al-Ayn on Friday morning, raising columns of smoke, seen by a journalist in Ceylanpinar on the Turkish side of the border, but none was seen after noon, and only sporadic gunfire was heard from inside the town. The US-negotiated agreement seemed at risk as Turkey and Kurdish fighters differed over what it required and whether combat had halted.

Calling his Syria approach "a little bit unconventional," Trump contended that Turkish President Recep Tayyip Erdogan as well as the Syrian Kurdish fighters the Turks are battling agree that the US-brokered cease-fire was the right step and were complying with it. Loading "There is good will on both sides & a really good chance for success," he wrote on Twitter. That optimism seemed at odds with Erdogan's own words. He told reporters in Istanbul that Turkish forces would resume their offensive in four days unless Kurdish-led fighters withdraw "without exception" from a so-called safe zone 30 kilometres deep in Syria running the entire 440-kilometres length of the border with Turkey.

There was no sign of any pullout by the Kurdish-led forces, who accused Turkey of violating the cease-fire with continued fighting at a key border town. Loading Replay Replay video Play video Play video They also said the accord covers a much smaller section of the border. And some fighters have vowed not to withdraw at all, dismissing the deal as a betrayal by the US, whose soldiers they have fought alongside against the IS. Eric Edelman, a former US ambassador to Turkey who served as the Pentagon's top policy official during the George W. Bush administration, said he doubts Turkey and its Syrian proxies could control the entire border area from the Euphrates to Iraq without help from Russia or others. "That's a very big expanse of territory to hold, albeit a lot of it is uninhabited," Edelman said. "That probably means they've cut already some deal with the Russians and the Iranians."

Even so, Trump insisted peace was at hand. "There is a cease-fire or a pause or whatever you want to call it," he said. "There was some sniper fire this morning," as well as mortar fire, but that was quickly halted and the area had returned to a "full pause," he said. Trump also asserted that some European nations are now willing to take responsibility for detained IS fighters who are from their countries. "Anyway, big progress being made!!!!" he exclaimed on Twitter.

Trump said nothing further about the European nations he now contends have agreed to take some of the IS fighters, a demand he has repeated often. No European government announced an intent to take control of IS prisoners. Loading Speaking in Brussels after briefing NATO ambassadors on the Syria situation, Secretary of State Mike Pompeo said, "We've seen comments today from a number of countries who said they may well be prepared to take back these fighters." He, too, identified no such countries. At the Pentagon, Defence Secretary Mark Esper said US troops are continuing their withdrawal from northern Syria. He also said no US ground troops will participate in enforcing or monitoring the cease-fire. "The force protection of our service members remains our top priority and, as always, US forces will defend themselves from any threat as we complete our withdrawal from the area," Esper told reporters.