US President Donald Trump urged Turkey to curtail its military operation in northern Syria and warned it not to bring US and Turkish forces into conflict on Wednesday but analysts said he has little leverage to halt its NATO ally's offensive there, Reuters reports.
Turkey's air and ground operation in Syria's Afrin region, now in its fifth day, targets US-backed Kurdish YPG fighters, which Ankara sees as allies of Kurdish insurgents who have fought in southeastern Turkey for decades.
Turkish President Tayyip Erdogan said he would extend the operation to Manbij, a separate Kurdish-held enclave some 100 km (60 miles) east of Afrin, possibly putting US forces there at risk and threatening US plans to stabilize a swathe of Syria.
Speaking with Erdogan by telephone, Trump became the latest US official to try to rein in the offensive and to pointedly flag the risk of the two allies' forces coming into conflict.
"He urged Turkey to deescalate, limit its military actions, and avoid civilian casualties," a White House statement said. "He urged Turkey to exercise caution and to avoid any actions that might risk conflict between Turkish and American forces."
The United States has around 2,000 troops in Syria.
Erdogan told Trump in the call that the United States must halt weapons support to the Syrian Kurdish YPG militia, the Turkish president's office said.
The offensive has opened a new front in Syria's multi-sided, seven-year-old civil war and complicated US efforts in Syria.
The United States hopes to use the YPG's control of the area to give it the diplomatic muscle it needs to revive UN-led talks in Geneva on a deal that would end Syria's civil war and eventually lead to the ouster of President Bashar Assad.
The United States and Turkey, while themselves allies in the North Atlantic Treaty Organization, have diverging interests in Syria, with Washington focused on defeating Daesh and Ankara keen to prevent Syria's Kurds from gaining autonomy and fueling Kurdish insurgents on its soil.
In the short-term, analysts say, the United States has little pressure it can apply on Turkey given the US military's heavy dependence on a Turkish base to carry out airstrikes in Syria against the Daesh militant group.
Its sway is further limited by the United States not having reliable military partners in Syria other than the Kurds, said Gonul Tol, director of the Center for Turkish Studies at Washington's Middle East Institute think tank.
The US needs Turkey not to spoil things…until now, Washington has walked a very fine line between working with the Kurdish militia and also preventing a complete breakdown in relations with Ankara,
A US official, speaking on condition of anonymity, said Trump values his relationship with Erdogan, but conceded that the US has limited leverage and that the administration is unlikely to commit more troops or covert operators to Syria, even if Turkey makes a move from Afrin to Manbij.
"The US has effectively said you can do this operation against Afrin because it is outside my area, but please keep it limited," said Bulent Aliriza, director of the Turkey Project at the Washington-based think-tank CSIS. "So it has not felt the need to go beyond the rhetorical means that it has employed."
Erdogan has looked to bolster ties with Russia and Iran in recent years, in part because of frustration with Washington's support for the YPG in the fight against Daesh.
Ankara sees the YPG as an extension of the outlawed Kurdistan Workers Party (PKK) insurgent group in Turkey which is deemed a terrorist organization by the United States, the EU and Turkey.
In a clear sign of rapprochement, Ankara is buying a S-400 missile defense system from Russia – unnerving NATO officials, who are already wary of Moscow's military presence in the Middle East. The S-400 is incompatible with NATO'S systems.
However, analysts say those moves are largely tactical and ultimately Turkey will be open to listening to US concerns about its military operation, given that Ankara needs the European Union for trade and NATO partners for its security.
I think behind closed doors, he really would not want a complete break in Turkey's relations with the West,
Max Hoffman, with the Center for American Progress, said the United States still had considerable leverage, and could look at imposing sanctions on Turkey in the future, should Turkish forces disregard warnings on Manbij.