The U.S. sanctioned Syrian Defense Minister Ali Abdullah Ayoub, the Treasury Department’s Office of Foreign Assets Control announced Thursday.

Ayoub has been added to the department’s Specially Designated Nationals And Blocked Persons List, and any of his assets subject to U.S. jurisdiction have been frozen. Americans are now generally prohibited from conducting business with him.

The designation comes amid a halt to the Syrian regime’s offensive on Idlib, in the country’s northwest, that has displaced some 900,000 people according to UN estimates.

Idlib falls within a de-escalation zone laid out in a deal between Turkey and Russia in late

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