The U.S. Federal Maritime Commission (FMC) is considering possible retaliatory measures against shipping linked to Spain after Spanish authorities prevented several U.S.-flagged vessels from docking at their ports.

The restrictions are part of a newly implemented Spanish policy that denies port access and airspace use to vessels or aircraft transporting weapons to Israel, as well as fuel tankers supplying fuel for Israel’s military use.

Why has this issue escalated?

Under this policy, Spain refused port entry to multiple ships registered under the U.S. flag. U.S. officials are now reviewing whether these actions constitute unfair or discriminatory practices under international maritime regulations.

Potential measures under review by the U.S. include:

• Financial penalties of up to $2.3 million per voyage
• Restrictions on cargo types or limits on voyages to and from U.S. ports
• In extreme cases, a ban on Spanish-flagged vessels entering U.S. ports

According to FMC findings, the initial investigation began nearly a year ago. In November 2024, reports confirmed that at least three U.S.-flagged vessels—Maersk Denver, Maersk Nysted, and Maersk Seletar—were denied access to Spanish ports. [freightwaves]

No final decision has been made so far. The FMC has stated that it is continuing to gather feedback and data from shipping companies and industry stakeholders before determining whether formal sanctions will be imposed.