BEIRUT — The Turkish government took the extraordinary step Wednesday of asking the United States to stop Kurdish commanders from diverting their forces from areas of eastern Syria to the fight in Afrin in the west.
The request followed an announcement from the Kurdish forces, which are allied with the United States in the fight against the Islamic State, that they intended to send 1,700 fighters from the strategically important eastern province of Deir El-Zour to the fight against Turkey in Afrin, a Kurdish enclave.
Ibrahim Kalin, a spokesman for President Recep Tayyip Erdogan of Turkey, said his country had taken “the necessary steps” through official channels and “expected from the United States that it should absolutely step in” to prevent the movement of the Kurdish forces from Manbij to Afrin. “This is our most natural right,” Kalin added.
It was not clear why Kalin had referred to Manbij, a city at the westernmost point of the Syrian territory held by the Kurds, though it might have been cited as a way station for the troops as they moved toward Afrin.
There was no immediate US response to the request by the Turks, a US ally and NATO member that invaded Afrin in January and threatened to drive the Kurds from the entire Syria-Turkey border. But the Turkish assault has since bogged down.
The fighting in Afrin is creating problems for the United States. The transfer of personnel from the Kurdish-led, US-backed militia known as the Syrian Democratic Forces, or SDF, is a blow to Washington’s effort to stamp out the last vestiges of the Islamic State.
On the diplomatic front, the Americans have insisted that while they are allied with the SDF in eastern Syria, they have no affiliation with the group in the northwest and will not aid any of its operations there.
But with its Kurdish coalition allies now streaming to join the defenders in Afrin, that posture will be increasingly difficult to maintain. As a result, in Afrin, the Trump administration is finding itself awkwardly on the opposite side from Turkey.
The SDF said in a statement Tuesday that it had made a “painful decision” to move the fighters from Deir El-Zour to Afrin, citing “the failure of the international community” to pressure Turkey and “stop its madness within our Syrian borders.”
The role in Afrin of the Kurdish militia known as the People’s Protection Units, or YPG, which is the main component of the SDF, has raised tensions with Turkey, which considers the militia an extension of a separatist group that is active in Turkey and is listed as a terrorist group by both Ankara and Washington.
For six weeks, Turkey has mounted a campaign to wrest control of Afrin from the YPG, an offensive that has displaced some 10,000 people and killed several hundred civilians and 41 Turkish soldiers. Erdogan said this week that 159 Syrians belonging to the Free Syrian Army, which is fighting alongside Turkish armed forces, had also died.
The YPG has responded with cross-border shelling, leading to civilian deaths in Turkey.
Adding to the complications, the YPG, which has carved out a zone of de facto autonomy from the Syrian government within Afrin and in a larger swath of northeastern Syria, last week allowed some pro-government militias to enter its territory to help the fight against Turkey.
The militias did not include formal army troops, but they flew the Syrian government flag. State television in Syria said the militias were aiding in the defense of the country’s borders but made no reference to Kurdish aspirations.
Turkey’s incursion came soon after the United States said that it would continue to support the SDF even after the fight against the Islamic State ends and that it would help the group form a border force to protect the long frontier its territory shares with Turkey.
Now, the movement of troops away from Deir El-Zour threatens two US objectives there: preventing a resurgence of the Islamic State; and curbing the growing influence of Iran, which sponsors militias that fight for the Syrian government.
In another crisis point in Syria, negotiations Tuesday between the government and Jaish al-Islam, the rebel group that controls the northern and eastern parts of the Damascus suburb of eastern Ghouta, went nowhere.
Despite mass civilian casualties and major territorial losses, the armed groups in the enclave refused to withdraw, according to anti-government activists.