Updated at 4:55 p.m. ET
Turkey is demanding that U.S. officials call off plans to meet with Mazloum Abdi, the Kurdish commander-in-chief of the Syrian Democratic Forces which fought alongside American troops to dislodge Islamic State insurgents from northeastern Syria.
"Our allies' dialogue with a terrorist wanted with a red notice is unacceptable," Turkish foreign minister Mevut Cavusoglu told Turkey's state-run Anadolu news agency Friday.
Turkish officials label Abdi, whose given name is Ferhat Abdi Şahin, a terrorist and link him to a separatist insurgency in Turkey known as the PKK, or Kurdish Workers Party. The U.S. State Department lists the PKK as a foreign terrorist organization.
"He is wanted for multiple terror attacks targeting the Turkish security forces, a NATO army, as well as civilians," Fahrettin Altun, Turkey's Director of Communications, told the Anadolu agency.
President Trump spoke with SDF commander by telephone on Wednesday and afterward praised the Kurdish general's "courage" in a tweet and addressed him directly, writing, "I look forward to seeing you soon."
Abdi, for his part, tweeted on Thursday that Trump had invited him to visit the U.S. "According to the circumstances on the ground," he added, "I will decide what to do in coming days."
A bipartisan group of senators that includes Democrats Chris Van Hollen of Maryland and Jeanne Shaheen of New Hampshire and Republicans Lindsey Graham of South Carolina and Marsha Blackburn of Tennessee wrote to Secretary of State Mike Pompeo Wednesday urging him to expedite a visa and any applicable waiver should Abdi seek to enter the U.S.
A visit from the SDF commander to the U.S. would likely trigger demands from Ankara that he be extradited to Turkey.
"Following President Recep Tayyip Erdogan's instructions," the Turkish state news agency reports, "Turkish Justice Minister Abdulhamit Gul Friday said Turkey would get in touch with U.S. officials regarding the terrorist's extradition if he entered the U.S. soil."
Despite the rising tensions between Washington and Ankara, Erdogan and Trump are still expected to meet at the White House on Nov. 13.
Meanwhile, Defense Secretary Mark Esper indicated Friday at NATO headquarters in Brussels that the removal of U.S. forces from Syria's northern border with Turkey earlier this month does not presage a complete U.S. pullout from Syria. "The United States will maintain a reduced presence in Syria," Esper said, "to deny ISIS access to oil revenue as we reposition for the next phase of the defeat ISIS campaign."
Esper did not confirm statements made by other U.S. officials Thursday that military tanks will be deployed to the oil fields which were recovered by U.S. and SDF forces after being occupied by ISIS insurgents. But he did allow that the U.S. military presence there would "include some mechanized forces."
Trump, for his part, continues to appear fixated on those oil fields. "Perhaps," he tweeted on Thursday, "it is time for the Kurds to start heading to the Oil Region!"
While U.S. troops will likely remain in Syria for some time, American officials involved in disaster relief assistance there are pulling out. "Staff from the U.S. Agency for International Development (USAID) originally based in Syria have redeployed out of the country," acting USAID spokesperson Pooja Jhunjhunwala said in a statement Friday, adding that those aid workers "continue to work on the U.S. Government's response to the humanitarian disaster in Syria."
In Moscow, Kremlin spokesman Dmitry Peskov said it was time for all U.S. forces to get out Syria. "As for the presence of American soldiers in Syria, our position is well known — only the Russian units are present in Syria legitimately at the invitation of the Syrian leadership," Peskov was quoted as saying by the Russian news agency TASS.
Russia is aligned with both Turkey and Syria, even though those neighboring nations are adversaries of each other, and it is now widely seen as the dominant foreign power in Syria.
As Russia moved additional forces and military aircraft into a newly declared "safe zone" along Syria's border with Turkey, there are reports from a British-based group, the Syrian Observatory for Human Rights, of continued clashes between Turkish-aligned forces in northern Syria and Syrian government forces as well as the Kurdish-dominated SDF.
Syria's state-run news agency SANA also reports that "forces affiliated to the Turkish occupation and its mercenaries" used artillery shells and mortars to attack the towns of Kowzaliyah and Tal Laban in the Tal Tamer region of northwest Syria.
Trump declared Wednesday he was lifting U.S. sanctions on Turkey because the NATO ally had agreed to what Trump termed "a permanent cease-fire" in northern Syria.
But SDF commander Abdi tweeted Thursday that Turkish forces continue their offensive in Syria, which began Oct. 9 after Trump ordered U.S. forces to leave the border area. He called on the guarantors of the cease-fire "to carry out their responsibilities."
Pentagon chief Esper condemned Turkey's invasion of Syria at NATO headquarters on Thursday, calling the incursion "unwarranted."
"Turkey has put us all in a very terrible situation," said Esper, as quoted by the Associated Press. "I think Erdogan was fixated on making this incursion for one reason or another and there was not a possibility that we were going to start a war with a NATO ally."
Trump has ruled out any role for the U.S. in patrolling a 20-mile deep "safe zone" along Syria's border with Turkey that Erdogan and Russian President Vladimir Putin agreed to establish while meeting Tuesday in the Russian city of Sochi.
According to the AP, German defense minister Annegret Kramp-Karrenbauer told her counterparts in Brussels Thursday the job of patrolling the "safe zone" could not be left only to Turkey and Russia. She advocated a broader international mission there.
"The Sochi agreement has not brought peace and it doesn't offer a basis for a political solution in the long run," Kramp-Karrenbauer told the AP. "We are looking for a solution that includes the international community."