WASHINGTON, October 15. /TASS/. Turkey’s military operation in northern Syria hampered efforts against the Islamic State terrorist group (outlawed in Russia), and led to the release of many captured militants, US Secretary of Defense Mark Esper said in a statement released on Monday.

"Despite the opposition and repeated warnings from the United States and the international community, Turkish President Erdogan ordered a unilateral invasion of northern Syria that has resulted in widespread casualties, refugees, destruction, insecurity, and a growing threat to U.S. military forces," Esper said.

According to the Pentagon chief, "this unacceptable incursion has also undermined the successful multinational "Defeat ISIS" mission in Syria, and resulted in the release of many dangerous ISIS detainees."

"Due to Turkey's irresponsible actions, the risk to U.S. forces in northeast Syria has reached an unacceptable level. We are also at risk of being engulfed in a broader conflict," Esper continued. "Therefore, at the President's direction, the Department of Defense is executing a deliberate withdrawal of U.S. military personnel from northeast Syria."

"Turkey's unilateral action was unnecessary and impulsive. President Erdogan bears full responsibility for its consequences, to include a potential ISIS resurgence, possible war crimes, and a growing humanitarian crisis," the secretary of defense said. "The bilateral relationship between our two countries has also been damaged."

NATO sanctions against Turkey

In his statement, Esper also said he would visit the NATO headquarters in Brussels next week, where he would "press" US allies to take collective measures against Ankara.

"I will be visiting NATO next week in Brussels, where I plan to press our other NATO allies to take collective and individual diplomatic and economic measures in response to these egregious Turkish actions," he said.

On October 9, Ankara launched an offensive in north Syria dubbed Operation Peace Spring, which began with airstrikes on Kurdish units. The objective is to establish a safety zone in northern Syria for protection of the Turkish border. In addition, Syrian refugees could return to that area from Turkey, Ankara believes. Syria’s SANA news agency slammed Ankara’s operation as an act of aggression. The world community has condemned Ankara’s actions.