The Trump Administration has launched a sharp attack on the International Maritime Organization’s (IMO) proposed Net-Zero Framework for shipping, branding it a “global carbon tax on Americans” imposed by “an unaccountable UN body.”

In a joint statement, Secretary of State Marco Rubio, Commerce Secretary Howard Lutnick, Energy Secretary Chris Wright, and Transportation Secretary Sean Duffy warned the United States would oppose the plan at the IMO’s October 2025 adoption meeting.

“President Trump will not accept any international environmental agreement that unfairly burdens the United States or harms American consumers,” the statement declared, signaling potential disruption to global shipping regulation.

The IMO proposal would set binding emissions limits and introduce greenhouse gas pricing across the maritime industry starting in 2027. It targets large ocean-going ships over 5,000 gross tonnage — responsible for roughly 85% of global shipping CO₂ emissions — requiring cleaner fuels and offset payments for vessels exceeding emissions thresholds.

The Trump Administration argues the plan would raise shipping and energy costs, penalize U.S. cruise and cargo operators, and benefit China by mandating expensive fuels that are not yet widely available. “Even small vessels would incur millions in fees,” the statement said. “We will not tolerate any action that drives up costs for our citizens or our industries.”

The administration also warned other IMO members to oppose the framework or face U.S. retaliation.

Industry groups are divided. The International Chamber of Shipping, representing more than 80% of the global merchant fleet, backs the IMO plan, calling it essential to accelerate cleaner fuel production. “The IMO must act in October to give industry the clarity and incentives needed to decarbonize,” said ICS Secretary General Thomas A. Kazakos.

Critics note Trump’s broader trade and tariff policies are already pushing up U.S. prices. “Tariffs are beginning to drive up consumer costs, and fewer imports will eventually mean fewer goods on store shelves,” said Jonathan Gold, Vice President at the National Retail Federation.

The IMO’s Net-Zero Framework would establish a fund to reward low-emission ships, support green infrastructure in developing nations, and shield vulnerable states from economic harm. Detailed implementation guidelines are expected in 2026, with enforcement beginning in 2027.

Trump’s stance comes as he nominates former National Security Adviser Mike Waltz as U.S. ambassador to the United Nations. Waltz, previously involved in maritime policy reform, is expected to carry the administration’s hard line on global shipping rules to New York.