Syria’s central bank has ordered commercial banks to freeze accounts associated with individuals and companies linked to the ousted regime of former President Bashar al-Assad.

A circular issued Thursday directs banks to report details of frozen accounts to the central bank within three working days. The order targets the Katerji Group, a prominent player in Syria’s oil trade, controlled by brothers Baraa and Hussam Katerji.

Baraa Katerji was killed in July during a suspected Israeli strike near Syria’s border with Lebanon—a strike that Israel has not publicly acknowledged. Hussam Katerji and his businesses are under US sanctions for allegedly facilitating oil shipments and financial backing for the Assad regime, according to the US Treasury. Attempts to contact Hussam Katerji were unsuccessful.

The Katerji brothers were part of a tight circle of businessmen who rose to prominence during the Syrian civil war, which began in 2011 following Assad’s violent suppression of anti-government protests. Assad was ousted on December 8 by Islamist rebels, who have since established an interim government and intensified efforts to trace financial flows tied to his administration.

A banker familiar with the situation, speaking anonymously, said implementing the directive could prove difficult. Many figures linked to the Assad regime reportedly used front companies or aliases to protect their assets.

Although the interim government had already frozen some accounts after taking power, certain individuals managed to circumvent the restrictions, withdrawing or transferring funds. A Syrian official explained that the new measures aim to be stricter and more precise, uncovering financial networks tied to the former regime and preventing further asset shielding.