U.S.-based Delta Crescent Energy and the Autonomous Administration of Northeastern Syria signed a deal for the extraction and sale of oil from territories under control of the U.S.-backed Syrian Democratic Forces (SDF), Al Monitor reported last week.

Turkey considers the SDF and its main armed force People’s Protection Units (YPG) to be affiliated with the Kurdistan Worker’s Party (PKK), an outlawed group that has fought for Kurdish self-rule for almost four decades.

“By this step, the PKK/YPG terrorist organization has clearly demonstrated its ambition to advance its separatist agenda by seizing the natural resources of the Syrian people,” the ministry statement said.

According to Ahval news agency Turkey also said that the United States was “disregarding international law, violating territorial integrity, unity and sovereignty of Syria, as well as being considered within the scope of financing terrorism.”

The agreement was signed “with the knowledge and encouragement of the White House,” an unnamed source had told Al Monitor, adding that the company had received an Office of Foreign Assets Control (OFAC) licence for its operations in Syria.

The same source said U.S. Special Envoy for Syria James Jeffrey had informed Turkey of the deal “repeatedly,” and that Turkey had “not reacted negatively.”

The SDF was the main force on the ground in the U.S.-led international initiative against ISIS, and controlled territory in northern Syria along the Turkish border, where Syria’s Kurdish population has historically been concentrated, until U.S. President Donald Trump greenlighted a Turkish incursion into the area last year.

“Despite the military partnership, (Syrian Kurds’) relationship with the Americans has always stood on slippery ground,” journalist Fehim Taştekin wrote in an article for news website Duvar on Monday.

Turkey’s Operation Peace Spring in northeast Syria showed that the partnership “could suddenly become expendable,” Taştekin said. “But the partnership in oil drops a small anchor to prevent such an outcome.”

Syrian Kurds tend to consider the oil deal to be “political recognition,” Taştekin said, “but the autonomous administration’s demand for recognition has not been met still.”

What the deal does do is confirm that the AANS is exempt from the U.S. Caesar Act sanctions against Syria for President Bashar al-Assad’s war crimes, Taştekin said. The deal could “affect the autonomous administration’s vision for Syria’s future.”

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