The United States on Wednesday said it launched an operation that could ultimately transfer up to 7,000 detainees affiliated with the Daesh terrorist group from northeastern Syria to neighboring Iraq to help ensure the terrorists remain in secure detention facilities.

The mission began as U.S. forces successfully transported 150 Daesh fighters held at a detention facility in northeastern Hasakah province to a secure location in Iraq, it said in a statement.

"Ultimately, up to 7,000 Daesh detainees could be transferred from Syria to Iraqi-controlled facilities," it added.

CENTCOM Commander Adm. Brad Cooper said the U.S. is "closely" coordinating with regional partners, including Iraq, and appreciates their role in ensuring the defeat of Daesh.

"Facilitating the orderly and secure transfer of ISIS detainees is critical to preventing a breakout that would pose a direct threat to the United States and regional security," he said, using an alternative acronym for Daesh.

In a deal reached Sunday that included a cease-fire and the integration of the Syrian Democratic Forces (SDF), which is dominated by the YPG/PKK terrorist group, into the state, Syrian President Ahmed al-Sharaa and YPG/SDF leader Ferhat Abdi Şahin agreed that the government would take over responsibility for prisoners accused of being part of Daesh.

Thousands of detainees are held in seven prisons in northeast Syria, while tens of thousands of people thought to be their family members live in the Al-Hol and Roj camps.

The United States, which heads an international coalition against Daesh while backing the YPG/SDF, said this week that the purpose of its alliance with the YPG/SDF had largely ended. Daesh was largely defeated in 2019.

Washington now supports Syria's new political authorities, which ousted the decades-old Baath regime, who are seeking to extend their control across the country after years of civil war.