Iran meanwhile offered on Saturday to engage Syrian Kurds, Syria's government and Turkey in talks to establish security along the Turkish-Syrian border following Turkey's military incursion into northern Syria to fight Kurdish forces.
On Friday, the Pentagon said USA troops came under artillery fire from Turkish emplacements though none of its soldiers were wounded near the Syrian border town of Kobani, 60 km (37 miles) west of the main area of conflict.
Syrian Kurdish forces appeared to be holding out in some areas of the town.
Separately on Saturday, IS declared a new campaign in Syria, which it said was to avenge its members' detention in Kurdish-run prisons.
On Friday in the Ibrahim sisters' Kurdish-held home city of Qamishli, Islamic State claimed responsibility for a deadly auto bomb, its first big attack since the Turkish assault began.
Turkish forces had stepped up their bombardment of Ras al-Ayn in their incursion, after U.S. troops in the region came under artillery fire from Turkish positions.
Turkey's assault on the Kurdish-controlled region of northeastern Syria has raised worldwide alarm over its mass displacement of civilians and the possibility of a revival by Islamic State in Syria.
"The US demands that Turkey avoid actions that could result in immediate defensive action", warned DeWalt. Other NATO allies Germany and France said they were banning weapons exports to Turkey.
As self-defense, the terrorists positions were targeted, Akar said.
However Russia and China on Friday blocked a UN Security Council statement drafted by Washington calling on Turkey to halt its offensive, diplomats told AFP. "All precautions were taken prior to opening fire in order to prevent any harm to the USA base. We say this is what happens when a country goes into a war of expansion so callously and rapidly".
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She said to me: 'I'm not pointing the finger" and I said: 'You have just annihilated me in public and hung me out to dry. Somebody said that it was the best thing that had ever happened, ever , on social media", Knightley said on Thursday.
An Iraqi Kurdish intelligence officer and senior Pentagon official said special forces operating on Mashtenur Hill in the major city of Kobani were hit by artillery fire fromTurkish forces conducting the so-called Peaceful Spring operation against Kurdish militants.
"Every kind of precaution was taken so no damage came to the USA base", he said.
Turkey launched airstrikes and ground incursions targeting Kurdish forces along the Turkey-Syria border on Wednesday after Trump announced Sunday - following a call with Turkish leader Recep Tayyip Erdoğan - that USA troops "will no longer be in the immediate area".
Before the speech, Trump was joined on stage by Andrew Brunson, an American pastor who was released by Turkey in October 2018 after almost two years of confinement.
Turkish President Recep Tayyip Erdogan has dismissed criticism of the operation, however, saying on Friday that Turkey "will not stop" the offensive "no matter what anyone says".
Prisoners of the Islamic State militant group (ISIS) held in Kurdish-controlled areas of north-eastern Syria are no longer the responsibility of the Syrian Democratic Forces (SDF), a spokesman for the group said.
Turkey said in a statement Friday that it opened fire after Kurdish forces launched rounds at them but stopped when the United States warned that the rounds were too close.
Asked about the Observatory report that rebels had killed a total of nine civilians on the road, he gave the same answer.
The Syrian government does not recognize the legitimacy of the Kurdish autonomy in the country's north-east, although Damascus has repeatedly condemned Turkey's occupational policies in the area.