The Treasury Department on Tuesday sanctioned 27 Iranian airlines and a handful of other entities as part of its ongoing effort to isolate Iran’s economy.

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The move comes as Tehran and its proxies continue to launch attacks in the Strait of Hormuz and the surrounding region, further entangling other countries in the U.S.’s more-than-six-month war and placing more pressure on global energy prices.

The latest U.S. action under “Operation Economic Outcast” targets all Iranian airlines that were not already facing sanctions.

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“Let this be a warning to anyone doing business with Iran’s remaining airlines, all of which we sanctioned today: You are at risk of being cut off from the global financial system,” Treasury Secretary Scott Bessent said in a statement.

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