Ankara does not want armed Kurds, whom they consider terrorists, to take part in the fight for Raqqa, but US military leaders have said that they are the most reliable fighting force on the ground in Syria.
Lt. Gen. Stephen Townsend, the top USA commander in the fight against ISIS in Syria and Iraq, said ISIS fighters had withdrawn from the towns and Syrian-Arab coalition troops had moved in.
This photo provided by the Russian Defense Ministry Press Service shows Russian air force Tu-22M3 bombers strike the Islamic State group wldtargets in Syria on Tuesday, Jan. 24, 2017.
The U.S. commander of coalition forces in Iraq and Syria says a Russian air strike in northern Syria accidently struck U.S. -backed Syrian Arab forces who are part of the fight against so-called Islamic State (IS) militants.
The U.S.is backing a force of Syrian Arabs and Kurds that is closing in on Raqqa, the de-facto capital in Syria of the Islamic State, which is also called ISIS.
The bombings stopped after US military officials called their Russian counterparts on an emergency line, which was set up in 2015 to avoid congested airspace in the area.
"I don't foresee us bringing in large numbers of coalition troops, mainly because what we're doing is in fact working", he said.
"Some quick calls were made through our de-confliction channels, and the Russians acknowledged and stopped bombing there", the general said.
Syrian regime forces, backed by Hizbullah fighters on the ground and air support from Russian Federation, recaptured the ancient city of Palmyra from Islamic State (ISIS) on March 2, the Syrian military said.
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He added: "It is a breakthrough for the club to say that but I do not want to think about what will happen to my future. Meanwhile, Huddersfield boss David Wagner felt his side didn't demonstrate their best qualities at the Etihad Stadium.
"This information was taken into account by the Russian command". Syrian, Russian and US forces all operate in the area, making unintended clashes very possible and common. Their role is now limited to advising local forces and staying behind front lines.
Russian Federation is using air power to prop up the regime of President Bashar al-Assad but also sometimes strikes IS.
Last August, Turkey launched a military operation in northern Syria to push ISIS off its southern border and keep Kurdish forces from advancing beyond the Euphrates river.
The key issue is North Atlantic Treaty Organisation ally Turkey's distrust of the Kurdish YPG forces, which comprise some 40 percent of the Syrian Democratic Forces.
"Essentially three armies have all converged within same grid square", Townsend told reporters in a teleconference from Baghdad.
Townsend said the United States is "still in decision-making stages" as to whether or not join the SDF assault on Raqqa "and what equipment they might need".
"The coalition supported Turkey and their partner-force efforts in al-Bab with more than 50 airstrikes, taking fighters off the battlefield, destroying [vehicle-borne homemade bombs], mortar and artillery pieces and denying the enemy use of dozens of vehicles, buildings, excavation equipment and weapons caches", he said.
Townsend said USA intelligence estimates put the number of IS fighters in Iraq and Syria combined at 12,000 to 15,000.