The U.S. said ​on Thursday (May 28, 2026) it has imposed new sanctions on Iran’s ‌military oil trade, even as Washington and Tehran ​reached a tentative agreement to ⁠extend their ceasefire and lift restrictions on shipping through the Strait of Hormuz.

The Treasury Department said it had sanctioned ‌eight vessels involved in transporting Iranian crude oil and petroleum products to global markets. The ‌vessels included the Marshall Islands-flagged oil tanker ‌Flora, ⁠the Comoros-flagged crude oil tanker Hauncayo and ⁠the Panama-flagged tanker Ill Gap.

“We will not allow the Iranian government to increase its oil revenue for the purpose ​of reconstituting its armed ‌forces and military capabilities,” Treasury Secretary Scott Bessent said in a release.

U.S. President Donald Trump has yet to approve the ceasefire deal on the war, ‌which the U.S. and Israel launched on ​February 28. The conflict has roiled global markets by closing the vital strait between ⁠Iran and Oman through which 20% of the world’s oil and gas has normally flowed.

The U.S. ‌also imposed sanctions on more than 15 entities, including Worth Seen Energy Limited in Hong Kong, Symphony Shipping and Maritime Management Inc. in Dubai, and Mehdiyev Trading Co., also in Hong Kong.

The Treasury Department said some of the sanctioned ‌Iranian entities also use the oil sales infrastructure of ​the Iranian armed forces to secure oil products from outside Iran. It said Worth Seen, ⁠for example, procures refined petroleum products for the National ⁠Iranian Oil Company on behalf of Sepehr Energy Jahan, the oil sales arm of ‌Iran’s Armed Forces General Staff, which the U.S. has previously hit with sanctions.

U.S. warns Oman

The ‌United States also warned Oman on ​Thursday (May 28, 2026) not ⁠to get directly or indirectly involved in any ‌effort to impose a toll ‌in the ‌Strait ⁠of Hormuz, saying ⁠it will penalise any partners involved in such ​a system.

“The ‌United States Government will not tolerate any effort to impose ‌a tolling system ​in the Strait of Hormuz,” Mr. Bessent said in ‌a post on X.

“Oman, in particular, should know that the U.S. Treasury will aggressively target ‌any actors involved – directly ​or indirectly – in facilitating tolls for ⁠the Strait and any willing ⁠partners will be penalised,” he added.