The International Maritime Organisation has taken a major step towards establishing a legally binding framework aimed at reducing greenhouse gas emissions from ships globally, with the goal of achieving net-zero emissions by around 2050.

The newly approved IMO Net-Zero Framework is the first initiative worldwide to combine mandatory emissions limits with GHG pricing across an entire industry sector. The measures, endorsed by the Marine Environment Protection Committee during its 83rd session (MEPC 83) held from 7–11 April 2025, include the introduction of a global fuel standard for ships and a global emissions pricing mechanism.

Scheduled for formal adoption in October 2025 and due to enter into force in 2027, the measures will apply to large ocean-going ships over 5,000 gross tonnage—vessels that are responsible for 85 percent of the total CO2 emissions from international shipping.

Closing the session, IMO secretary-general Mr Arsenio Dominguez praised the spirit of collaboration shown by Member States and commented:

“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 modernize shipping and demonstrates that IMO delivers on its commitments. 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.”

Key Elements of the IMO Net-Zero Framework

The Net-Zero Framework will be incorporated as a new Chapter 5 in Annex VI of the International Convention for the Prevention of Pollution from Ships. MARPOL Annex VI already includes mandatory energy efficiency requirements and has 108 Parties, covering 97 percent of the world’s merchant shipping fleet by tonnage.

The framework aims to meet the climate goals outlined in the 2023 IMO Strategy on the Reduction of GHG Emissions from Ships, accelerate the adoption of zero and near-zero GHG fuels and technologies, and promote a just and equitable transition.

Under the draft regulations, ships will need to comply with:

• Global Fuel Standard: Vessels must progressively reduce their annual greenhouse gas fuel intensity, using a well-to-wake measurement of GHG emissions per unit of energy.

• Global Economic Measure: Ships exceeding the GFI thresholds must acquire remedial units to offset their excess emissions, while vessels using zero or near-zero GHG technologies will be rewarded financially.

Ensuring Compliance

Compliance with the GHG Fuel Intensity targets will be measured against two benchmarks: a Base Target and a Direct Compliance Target, where vessels reaching this higher standard may earn surplus units.

Ships failing to meet targets can balance their emissions deficit by:

• Transferring surplus units from compliant ships;

• Using previously banked surplus units; or

• Purchasing remedial units through contributions to the IMO Net-Zero Fund.

The IMO Net-Zero Fund

The IMO Net-Zero Fund will collect contributions from emissions pricing and allocate funds to:

• Reward low-emission ships;

• Support innovation, research, and infrastructure development, especially in developing countries;

• Fund training, technology transfer, and capacity building to advance the IMO’s GHG Strategy; and

• Mitigate negative impacts on vulnerable states, such as Small Island Developing States and Least Developed Countries.

The IMO’s decision marks a historic milestone, setting a precedent for industry-wide climate action and reinforcing the organisation’s role in driving the decarbonisation of global shipping.

For more information visit www.imo.org