Turkish officials reportedly sought an explanation for Milley's surprise visit on Saturday to an undisclosed US base in the Kurdish-controlled region of Syria.
"We can confirm that Amb. Flake did go to the Turkish Ministry of Foreign Affairs for meetings," State Department press secretary Ned Price told reporters Monday afternoon.
"It's our understanding that Gen. Milley met only with US troops while in Syria," Price said.
Milley, who serves as the Chairman of the US Joint Chiefs of Staff, inspected security measures and met with the top commander of US forces in Iraq and Syria, Army Maj. Gen. Matthew McFarlane. He did not meet with representatives of the Kurdish-led Syrian Democratic Forces (SDF), Pentagon spokesperson Col. Dave Butler told Al-Monitor.
The top general's trip came as Biden administration officials signal their intention to keep the roughly 900 US troops in Syria in support of the SDF in order to keep pressure on the remnants of the Islamic State group, which no longer controls significant territory, but maintains a low-level insurgency that aims to reconstitute, defense officials say.
It also came as Pentagon officials led by defense chief Lloyd Austin are touring the Middle East to meet with troops and assure allies of Washington's commitment to security in the region.
But word of Milley's visit threatened to rekindle accusations by Turkey's government over US support for the SDF, as President Recep Tayyip Erdogan faces perhaps his toughest re-election bid yet in June.
Ankara considers the Syrian People’s Protection Unit (YPG) — a largely Kurdish militia that leads the SDF — to be inextricable from the Kurdistan Workers' Party, or PKK – a designated terrorist organization by Turkey and Western allies.
The US does not consider the YPG to be a terrorist group and has funded, armed and trained the militia to fight against the Islamic State on the ground in Syria since 2015.
The campaign was largely a success, but issue remains one of the thorniest between the two NATO allies.
The SDF insists it poses no threat to Turkey, and has said it is open to negotiations with the Turkish government. Ankara has repeatedly called on Washington to end its support for Syrian Kurdish groups and to withdraw its troops from the country as Ankara explores rapprochement with the Bashar al-Assad regime in Damascus.
According to Al-Monitor Washington, for its part, has sought to avert another potential Turkish military operation against the YPG in northern Syria, saying the move would undermine efforts to contain IS. Some 10,000 IS fighters remain imprisoned in makeshift facilities guarded by the SDF in northeast Syria.
Turkey's President Recep Tayyip Erdogan has toned down his repeated threats to launch a fresh incursion in recent months amid opposition from the US and Russia, which also maintains troops in Syria and limited ties with the YPG.
At least two Turkish air and drone strikes amid a blitz against Syrian Kurdish forces last November came dangerously close to US troops, leading CIA director Bill Burns to warn his counterpart in Ankara.
Syrian Kurdish officials have worried the Turkish army may launch its long-anticipated assault this spring as Erdogan's AKP party seeks to consolidate its nationalist voter base ahead of the pivotal elections.
Turkey-US relations have been fraught by a handful of high-profile disagreements in recent years, including Ankara’s purchase of Russia's S-400 air defense systems, new military basing access for the US military in Greece and Turkey delaying Sweden and Finland's accession to NATO amid the war in Ukraine.
Ties between the two allies have been buoyed somewhat by Turkey's role mediating an agreement with Russia restore Ukraine's grain exports as well as by rapid US support for Ankara's emergency rescue efforts following last month's earthquake, which was the deadliest to hit Turkey in decades.
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