The Kurdish-led Syrian Democratic Forces (SDF) has urged its U.S. allies to assume their "moral obligations" as the cross-border Turkish offensive continues, while European countries intensified pressure on Ankara and Russia called for those "present illegally" in Syria to leave.

'Moral obligations'

The SDF called on allies "to fulfil their duties and assume their moral obligations" and to protect them by "closing the air space to Turkish warplanes" in a statement issued on Saturday.

"Our allies had guaranteed us protection ... but suddenly and without warning they abandoned us in an unjust decisions to withdraw their troops from the Turkish border," the statement read.

The SDF were the main ground partner in the protracted U.S.-led campaign against ISIL in Syria, losing 11,000 fighters before finally overrunning its self-proclaimed "caliphate" in March.

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Over 100,000 displaced in Turkish offensive

The BBC quoted senior official Redur Xelil as saying that guarding ISIL prisoners was "no longer a priority" for the SDF. 

"Guarding ISIL prisons is no longer a priority. Whoever cares about the secure detention of the prisoners they are welcome to come and find a solution." 

He warned that the Turkish offensive was opening the door to ISIL to regroup.

Pressure on Trump 

The Turkish offensive began after U.S. President Donald Trump on Monday ordered American troops to pull back from the border. He stands accused of giving Turkey's operation a green light.

Trump has since toughened his policy towards Ankara after an outcry from both sides of the political aisle in Washington, and on Friday threatened crippling sanctions if the operation goes too far.

The SDF on Saturday down-played the impact sanctions would have on the ground, saying they would not prevent Turkey from pressing ahead with its operation. 

European opposition grows 

France and Germany on Saturday suspended arms exports to Turkey, meanwhile, as protesters denounced Ankara at rallies in several European cities.  

France said it had suspended all planned exports of "war materials" to Turkey that could be used in the offensive into Syria. "In expectation of the end of this offensive, France has decided to suspend all plans to export to Turkey weapons that could be used in this offensive. This decision is with immediate effect," a joint statement from the defense and foreign ministries read.

Germany, one of Turkey's main arms suppliers, earlier said it had suspended exports. Finland, Norway and the Netherlands have already announced that they are stopping arms exports to the country. 

A meeting in Luxembourg on Monday of the European Union's foreign affairs committee will decide on a coordinated European approach to the issue. 

Putin on 'illegally present'

Russian President Vladimir Putin has said those "illegally present" in Syria should leave the country, and indicated that Moscow would withdraw troops if a "future legitimate government" made such a request. 

"Those who are illegally present in a foreign country, in this case, in Syria, should leave the region. It concerns all countries," he said in an interview with Al Arabiya, Sky News Arabia and RT.

"If Syria's future legitimate government says that it doesn't need Russian troop to remain in the country, it will also concern Russia."

Mounting casualties

Turkish air strikes on Kurdish-held towns and intense artillery exchanges have caused mounting casualties on both sides of the border since Wednesday.

On the Syrian side, 28 civilians and 74 SDF fighters have been killed by Turkish bombardment, according to the Britain-based Syrian Observatory for Human Rights.  

On the Turkish side, 17 civilians have been killed by cross-border artillery attacks, according to Turkish reports. 

The United Nations has said 100,000 people in northeast Syria have been displaced by the violence, while the Syrian Kurdish-led administration in the region on Saturday put the number at 191,069.

(With input from Reuters)