Turkey's BDDK banking watchdog revoked the operating license of Iranian lender Mellat Bank's branch in Istanbul, according to a notice published in the Official Gazette on Saturday, as the US presses other countries to increase economic pressure on Tehran.

"It has been decided to revoke the operating license of Bank Mellat, Head Office in Tehran, Istanbul Turkey Central Branch," the notice said, without citing the US measures or any operational issues.

It said the decision was taken under a clause of Turkey's banking law, which allows a bank's license to be revoked or withdrawn if its continued operation is deemed to pose a risk to depositors' rights or the security and stability of the financial system.

US sanctions Turkish bank for Iranian ties

Earlier this month, the US Treasury Department imposed sanctions on a small Turkish investment bank and two subsidiaries. The Treasury also said Turkey and Oman had decided to stop flights by Iranian airline Mahan Air to their countries as a result of discussions held with both countries on complying with US measures against Iran.

The entities targeted are Istanbul-based investment bank Golden Global Yatirim Bankasi Anonim Sirketi, asset manager Golden Global Portfoy Yonetimi Anonim Sirketi, and asset leasing company Golden Global Varlik Kiralama Anonim Sirketi, according to the Treasury's Office of Foreign Assets Control.

A general view of the Treasury Building on day two of a partial government shutdown in Washington, DC, US, February 1, 2026.
A general view of the Treasury Building on day two of a partial government shutdown in Washington, DC, US, February 1, 2026. (credit: KEN CEDENO/REUTERS)

The sanctions put all three entities on the Treasury's OFAC Specially Designated Nationals list, cutting them off from the dollar-based financial system.

The Treasury Department also issued a general license to allow the wind-down of transactions with the sanctioned entities.

In an interview with news outlet America's Voice News, US Treasury Secretary Scott Bessent said that the latest action "is code for you are out of business."