Oct. 15 (UPI) -- Pentagon chief Mark Esper assailed the Turkish regime Tuesday for its military offensive in Syria, calling it an "unacceptable incursion" that has undermined coalition efforts to defeat terrorism in the battle-scarred nation.
The Trump administration has denounced the offensive for days, since Turkey launched Operation Peace Spring a week ago. The criticism, however, has been rejected by some who blame the administration for allowing the invasion to start in the first place.
"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 said in a statement. "Therefore, at the president's direction, the Department of Defense is executing a deliberate withdrawal of U.S. military personnel from northeast Syria."
Esper called President Reccep Tayyip Erdogan's offensive "unnecessary and impulsive" and said the nations' relationship has been damaged. Esper added that he will travel to Belgium next week to urge diplomatic and economic responses among NATO allies.
"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, adding Erdogan will bear full responsibility for an Islamic State resurgence or a humanitarian crisis.
Due to the U.S. withdrawal, Russian military forces are now patrolling areas of fighting in northeastern Syria between Turkish and Kurdish troops.
Moscow's Defense Ministry said its military police in the Kurdish town of Manbij were patrolling along the Syria-Turkey border and interacting with Turkish authorities. Russian troops entered the town with Syrian government forces loyal to President Bashar al-Assad.
Russia, which has been a military ally to Assad, is stepping into the zone after the exit of U.S. troops. It was reported Monday Kurdish forces had agreed to cede Manbij in exchange for protection. The deal allows Syrian government forces to take over security in some border areas while the Kurds would control local institutions. The Kuridstan Workers party has also formed a pact with Russian officials.
U.S. President Donald Trump and his administration, perhaps feeling escalating bipartisan pressure over the decision to pull American troops, have demanded Turkey stop fighting and implement a total cease-fire -- something Turkish officials have so far rejected.
"You cannot talk or negotiate with terrorists," Turkish Vice President Fuat Oktay told Sky News Tuesday.
"[Negotiations are] unrealistic and I wish they (Europe and NATO partners) would change their policy."
Trump imposed sanctions against the regime in Ankara on Monday as a punitive measure.
The military incursion is intended to clear a swath of land along its border with Syria in an effort to return millions of Syrian refugees who emigrated to Turkey.
"Anyone who opposes us should understand Turkey first," Oktay said. "This is unsustainable."
U.S. Vice President Mike Pence said Monday he will lead a delegation to Turkey in the "immediate future" in an effort to end the violence.
The fighting led the Kurdish Red Crescent to pull staff out of northeast Syria, which left displaced populations with "extremely limited support." Mercy Corps also suspended operations and evacuated staffers.
European Union members announced Monday they would halt arms exports to Turkey to interrupt fighting. Tuesday, Britain suspended arms sales to Turkey, following similar moves by France and Germany.
Newsweek reported Tuesday the Pentagon will help Russian forces establish themselves in Manbij. The report said U.S. personnel have been "assisting the Russian forces to navigate through previously unsafe areas quickly."