Will President Trump Block IMO Global Maritime Climate Plan?
The International Maritime Organization (IMO) has moved a step closer to introducing the world’s first legally-binding climate framework for an entire industry sector, setting mandatory GHG limits and implementing global emissions pricing.
The decision, made during the Marine Environment Protection Committee’s 83rd session (MEPC 83) in April, signals a significant shift for the US maritime industry, which now faces both opportunities and challenges under the proposed rules.
Despite the opportunity, President Donald Trump “has made it clear that the US will not accept any international environmental agreement that unduly or unfairly burdens the US or harms the interests of the American people".
The IMO’s net-zero vision
The draft amendments to MARPOL Annex VI would enshrine the IMO net zero Framework into a new Chapter 5, aiming for net-zero emissions from international shipping by or around 2050.
This aligns with the organisation’s 2023 GHG Strategy, prioritising the adoption of zero and near-zero GHG fuels, advanced technologies and cleaner energy sources.
“The approval of draft amendments to MARPOL Annex VI mandating the IMO net zero framework represents another significant step in our collective efforts to combat climate change, to modernise shipping and demonstrates that IMO delivers on its commitments,” said Arsenio Dominguez, IMO Secretary-General, as he closed the meeting.
“Now, it is important to continue working together, engaging in dialogue and listening to one another, if we are to create the conditions for successful adoption.”
Two core measures underpin the framework:
- Global fuel standard: Progressive reduction of a ship’s annual greenhouse gas fuel intensity, calculated on a well-to-wake basis
- Global economic measure: A pricing system where ships exceeding GHG thresholds purchase remedial units, while low-emission ships earn financial rewards.
These rules will apply to large ocean-going vessels of more than 5,000 gross tonnage, covering 85% of CO₂ emissions from international shipping.
If adopted in October 2025, the measures would enter into force in 2027.
Economic implications for the US
The framework includes the creation of an IMO Net-Zero Fund, designed to reward low-emission ships, invest in innovation and infrastructure and support a just transition in developing nations.
However, the US government has voiced strong opposition. President Trump has described the measures as “effectively a global carbon tax on Americans levied by an unaccountable UN Organisation".
In an official statement by the US Department of State, Trump says the fuel standards would "conveniently benefit China by requiring the use of expensive fuels unavailable at global scale".
The statement continues: “These standards would also preclude the use of proven technologies that fuel global shipping fleets, including lower emissions options where U.S. industry leads such as liquified natural gas (LNG) and biofuels.”
The administration also warns that “ships will have to pay fees for failing to meet unattainable fuel standards and emissions targets," adding: "These fees will drive up energy and transportation and leisure cruise costs. Even small vessels would incur millions of dollars in fees, directly driving up costs for American consumers.”
The Trump Administration “unequivocally rejects” the proposal by the IMO.
Path to adoption
The timeline is clear:
- October 2025: Expected adoption at an extraordinary MEPC session
- Spring 2026: Approval of detailed implementation guidelines
- 2027: Framework enters into force, 16 months after adoption.
For US ports, ship operators and logistics providers, the lead-up to 2027 will be a critical period to assess compliance strategies, explore alternative fuels and factor in potential cost increases.
Maritime environmental measures
MEPC 83 also advanced other environmental protections, including a 2025 Action Plan to combat marine plastic litter, work on a legally binding biofouling management framework to curb invasive species and steps towards designating new Emission Control and Particularly Sensitive Sea Areas.
The IMO net zero Framework represents a transformative regulatory development for the maritime sector, combining emissions caps with market-based incentives.
For the US, it poses a dual challenge, aligning with global decarbonisation goals while safeguarding economic competitiveness.
The outcome of the October 2025 session will determine whether US operators adapt to new sustainability standards or continue to push for exemptions and alternative approaches.