Omar Haj Kadour, AFP | A picture taken on October 13, 2017, shows the Syrian city of Afrin (bottom) next to a three-metre high fortification, built by the Turkish government along its border with Syria.

Turkey opened a new front in Syria's war on Saturday, launching airstrikes against a US-backed Kurdish militia in Afrin province that raise the prospect of a further strain on relations between Ankara and Washington.

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The operation, which the Turks dubbed "Operation Olive Branch", pits Ankara against Kurdish fighters allied to the United States at a time when ties between Turkey and Washington -- NATO allies and members of the coalition against the Islamic State group -- appear dangerously close to a breaking point.

The strikes on the Syrian-Kurdish YPG militia hit some 108 targets, the Turkish military said. On land, the Turkey-backed Free Syrian Army rebels were also helping the operation in Afrin, a senior Turkish official said.

"The weakening of the region with artillery fire is under way. The first stage was carried out by aerial forces of the military and nearly all of the targets were destroyed," Prime Minister Binali Yildirim said.

From Sunday land forces would also carry out "necessary activities", depending on developments, he said.

The YPG said the strikes killed six civilians and three fighters. One of the fighters belonged to the YPG and two were from its all-female affiliate, YPG spokesman Birusk Hasaka said. The attacks also wounded 13 civilians, he said.

"We will defeat this aggression, like we have defeated other such assaults," the group said in a statement.

Turkish army ''shells Kurdish positions'' in Syria's Afrin

Turkey confronting US allies

The YPG has been the key US ally in the fight against IS jihadists, playing a key role in pushing the extremists out of their Syrian strongholds.

The US reaction to the strikes on Saturday was cautious. The Pentagon said the United States urged those involved to focus instead on the fight against Islamic State. A Pentagon official said: "We encourage all parties to avoid escalation and

to focus on the most important task of defeating ISIS."

Russia, meanwhile, has voiced concern and is withdrawing its troops from Afrin. "Moscow is concerned at this news. We call on the opposing parties to show restraint," the foreign ministry said in a statement after the launch of an operation that has also drawn US warnings.

The Russian defence ministry said its troops were withdrawing from the area "to prevent potential provocation and exclude the threat to the life and wellbeing of Russian military".

Russia says it is withdrawing its troops from Syria''s Afrin region

(FRANCE 24 with AFP, AP and REUTERS)

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