Binding Global Climate Legislation

On 11 April 2025, a legally binding global climate agreement was adopted by the International Maritime Organization (IMO), the UN body that regulates global shipping. The United States did not vote but walked out, warning others to follow or face consequences, but 63 nations stayed and approved new regulations to cut greenhouse gas emissions across the maritime sector—one of the most polluting and least regulated industries on Earth. The deal mandates a trajectory to net-zero emissions by 2050, backed by financial penalties and a structured compliance framework with enforcement. Shipowners who fail to meet emissions reduction targets will pay up to $380 per tonne of CO₂ equivalent, feeding into a new Net-Zero Fund to support the transition and ensure climate justice within the sector.

This important step towards establishing a legally binding framework to reduce greenhouse gas (GHG) emissions from ships globally is the first in the world to combine mandatory emissions limits and GHG pricing across an entire industry sector. The measures include a new fuel standard for ships and a global pricing mechanism for emissions. They should enter into force in 2027, becoming mandatory for large ocean-going ships over 5,000 gross tonnage, which emit 85% of the total CO₂ emissions from international shipping.

The IMO Net-Zero Framework will be included in a new annex chapter of the International Convention for the Prevention of Pollution from Ships (MARPOL), which currently has 108 Parties, covering 97% of the world’s merchant shipping fleet by tonnage, and already includes mandatory energy efficiency requirements for ships. The goal is to accelerate the introduction of zero and near zero GHG fuels, technologies and energy sources, and support a just and equitable transition.

The IMO Net-Zero Fund will collect pricing contributions from emissions to reward low-emission ships; support innovation, research, infrastructure and just transition initiatives in developing countries; fund training, technology transfer and capacity building; and mitigate negative impacts on vulnerable States, such as Small Island Developing States and Least Developed Countries.

SOURCE: based in part on https://www.imo.org/en/MediaCentre/PressBriefings/pages/IMO-approves-ne…