The US government has unveiled its Maritime Action Plan (MAP), reviving proposals to impose port fees on foreign-built vessels calling at American ports.

Designed to restore what President Trump described in his April executive order as “America’s maritime dominance,” the plan sets out a broad strategy to strengthen the domestic shipping industry. Measures include incentives for investment in US shipyards, expanded training programmes for mariners and regulatory reforms aimed at stimulating domestic maritime trade.

A key element of the strategy is the introduction of a port fee on foreign-built ships operating in US trades. Framed as a national security measure, the proposal argues that vessels constructed overseas but benefiting from access to US markets should contribute to rebuilding the country’s maritime industrial base. Under the plan, these ships would pay a security levy each time they call at a US port.

Rather than applying a flat fee, the MAP proposes calculating the charge based on the weight of imported cargo carried by the vessel. The document outlines illustrative scenarios, suggesting that a fee of one cent per kilogram could generate approximately $66bn over a decade, while a 25-cent-per-kilogram levy could raise close to $1.5tn over the same period.

The plan does not clarify how it relates to a separate port fee introduced by the US Trade Representative in October 2025. That measure, which also targeted non-US-built ships, was suspended until November 2026 following US-China trade talks and retaliatory tariffs from Beijing, leaving its long-term status unclear.

As a strategic blueprint rather than draft legislation, the MAP leaves several critical issues unresolved — including implementation timelines and how the financial burden would be shared between carriers and cargo owners — prolonging uncertainty across the maritime sector.