WASHINGTON— Recent military moves by Turkey and the United States in Syria have strained the long-standing relationship between the allies, regional experts at a Turkish Heritage Organization panel said Wednesday.

Earlier this month, Turkey began an offensive to push the People’s Protection Units, a U.S.-backed Kurdish militia in Syria known as the YPG, out of the northern Syrian town of Afrin near the Turkish border. Turkey sees the YPG as a threat because of its ties to the terrorist organization called the Kurdistan Workers’ Party, also known as the PKK.

This was the latest conflict that put Turkey at odds with the U.S., which announced last May that it would arm the YPG in an effort to defeat ISIS in Syria.

At the panel, former U.S. Marine Corps Commandant Gen. (Ret.) James Conway and former Turkish Embassy in Washington Armed Forces Attache Major Gen. (Ret.) Ahmet Bertan Nogaylaroglu sought to emphasize the common military interests between the two allies. Since the 1950’s, Turkey’s strategic position between three continents, and American military interests, have formed the basis of the partnership.

“We are a front line, so we are not the same as Holland, Germany and other countries,” Nogaylaroglu said.

At the heart of the conflict lies the PKK, which Nogaylaroglu said has links to the YPG militia in Syria. Turkey has battled the group since 1984.

While the two former generals are confident that the nations’ relations will eventually return to normal, Sinan Ciddi, the executive director of the Institute of Turkish Studies at Georgetown University, is less optimistic. He said U.S.-Turkish military leaders remain in close contact, but that the diplomatic relations are at a “breaking point.”

Turkey recently alleged that American transcripts of a phone call between Turkish President Recep Tayyip Erdogan and President Donald Trump addressing the Afrin operation were inaccurate, according to CNN.

“When there have been previous disagreements or crises between the countries, you either had civil servants, bureaucrats, diplomats, ambassadors, that work the problem behind the scenes,” Ciddi said. “If all those fails, you would at least have the head of government speaking to each other at the very end to basically smooth out disagreements… This is probably the worst the bilateral relationship has ever been.”

Both Nogaylaroglu and Conway said U.S.-Turkish relations will eventually return to normal because of the latter’s strategic geographic location at the intersection of three continents. Both nations are members of NATO, providing a long term reason to cooperate.

Yet Ciddi says Turkey is now questioning its standing as a NATO ally.

Before the Turks attacked Afrin, they had requested a border force on the Turkish-Syrian border to defend against YPG attacks, to which the Americans said no, enraging the Turkish government, Ciddi said. Turkey then sought the permission of the Russians, who granted it, Ciddi added. But the Turks didn’t ask their American counterparts, a break from longstanding practice between the allies.

“This is a golden opportunity for Russia to continue driving a wedge between Turkey and (NATO), and they’re succeeding,” Ciddi said.”

Russia says hundreds have been killed in Afrin, Syria during a Turkish operation to remove the Kurdish YPG militia from the city.

“It’s gotten infinitely more complicated when the Russians got involved,” Conway said.