The waivers to the more than century-old Jones Act were ​issued by Trump during the Iran conflict to help ease supply disruptions ​and keep fuel and other critical goods moving between U.S. ⁠ports in an attempt to moderate rising prices. Lawmakers now say ​those emergency conditions have passed and the waivers should end on schedule.

In ​their letter, Johnson and 51 other Republican lawmakers emphasize the importance of the Jones Act, which requires cargo moving between U.S. ports to be carried on American-built, owned, ​and crewed ships.

They argue that the law supports U.S. maritime jobs ​and national security, and warn that continued waivers could weaken domestic shipping by allowing foreign-flagged ‌vessels ⁠to operate in coastal trade even when U.S. ships are available.