IMO meeting to decide on the maritime CO2 tax
The International Maritime Organization (IMO) will meet this week to decide whether to formally impose a maritime CO2 tax. While the European Union, the United Kingdom, Japan, and China support the measure, the United States has strongly opposed it, threatening tariffs, visa restrictions, and port taxes against governments that back the initiative.
The IMO, a United Nations agency responsible for international maritime safety and pollution prevention, reached a preliminary agreement in April 2025 on a regulatory package aimed at curbing emissions from the most polluting ships. The plan introduces a binding global framework that sets mandatory emission limits and a pricing mechanism for greenhouse gases generated by the shipping sector. However, several small island nations and environmental NGOs argue that the agreement still lacks ambition and falls short of the Paris Agreement’s climate goals.
In 2024, international shipping accounted for 1.4% of total global greenhouse gas emissions. Ships release more than one billion tons of CO2 equivalent each year, according to Clarkson Research Services Ltd.
Under the proposed IMO regulation, ships weighing over 5,000 tons that exceed a specific emissions threshold would be required to pay a levy, while cleaner vessels could benefit from rewards and incentives. Ships emitting more carbon than the defined limit would face penalties. The new requirements are technically set to take effect in 2027, but payments would not begin until 2029.
If adopted, the regulation would impose a CO2 tax on the most polluting ships. Formal approval of the agreement is still needed, which is why the topic will be central at the IMO’s Marine Environment Protection Committee meeting scheduled for October 14–17. The U.S. government is also expected to participate in this week’s session.
The U.S.-EU standoff on global shipping emissions
In recent months, Washington has worked to block the proposal, threatening port duties and visa restrictions against supportive nations. According to reports, the U.S. State Department has contacted several IMO member states, urging them not to adopt the Net-Zero Framework.
“The United States will move to impose corrective measures on nations sponsoring this neocolonial export of global climate regulations led by Europe,” the State Department said on October 11. Meanwhile, the European Commission has reiterated its call for the IMO to move forward with the regulation. As a result, the European Union and the United States approach this week’s vote sharply divided.
This dispute unfolds amid broader trade tensions between Brussels and Washington. The two sides are currently negotiating the next steps in an agreement reached earlier this year concerning 15% tariffs on most EU products entering the U.S.
Proceeds from the measure would go to the IMO’s Net-Zero Fund, according to the draft regulation. Although the exact allocation and redistribution of these funds remain unclear, researchers at University College London estimate that the levy could generate $11–12 billion per year, as most ships would likely be unable to avoid penalties during the early implementation years.