The 84th Session of the IMO Marine Environment Protection Committee (MEPC 84) convened at IMO Headquarters, London, from 27 April to 1 May 2026, under the chairmanship of Harry Conway (Liberia). This report, prepared by the PATNA Initiative, provides a detailed look at what happened during the session, the results, and their implications for global maritime environmental governance, especially for African and developing states.
MEPC 84 proved to be one of the most consequential sessions in the Committee’s recent history, spanning five high-intensity days of technical and political negotiation. The session’s agenda encompassed greenhouse gas (GHG) reduction, air pollution and energy efficiency, ballast water management, marine plastic pollution, underwater radiated noise, pollution prevention and response, and the designation of particularly sensitive sea areas.
The main issue of the session was the disputed future of the IMO Net-Zero Framework (NZF), a legally binding set of changes to MARPOL Annex VI that was adopted at MEPC 83 but postponed after a procedural vote at the Extraordinary Session in October 2025. Over two full days, delegations representing three broadly defined positions engaged in the Committee’s most extensive GHG debate in recent history. No formal agreement on the NZF was reached; however, the Committee established a strengthened intersessional work programme comprising two additional ISWG-GHG sessions scheduled for September and November 2026, with terms of reference designed to keep all proposals within scope. Formal adoption of any agreed measure is unlikely before 2027.
In a landmark procedural development, MEPC 84 adopted a resolution condemning unlawful interference with commercial shipping in the Strait of Hormuz, carried by roll-call vote with 59 in favour, 3 against, and 32 abstentions, marking only the second or third such vote in MEPC history. The Secretary General committed to mobilising emergency response mechanisms to address the humanitarian and environmental risks facing approximately 20,000 stranded seafarers aboard some 2,000 ships.
On marine plastic pollution, the session marked a decisive breakthrough: the Committee instructed the PPR Sub-Committee to develop a mandatory code for the carriage of plastic pellets in freight containers, establishing for the first time a concrete, time-bound regulatory pathway. A package of amendments to MARPOL Annex VI was formally adopted, including the designation of the North East Atlantic as a new Emission Control Area, with entry into force set for 1 September 2027. Significant technical progress was also recorded on methane and nitrous oxide measurement guidelines, the CII Phase 2 review, ballast water management, underwater radiated noise governance, and new regulatory outputs on ozone-depleting substances and Maritime Autonomous Surface Ships.
This report is grounded in official IMO documents, session transcripts, and publicly available intervention records to help policymakers, delegates, and stakeholders understand what happened at MEPC 84 and its implications for maritime, economic, and environmental interests.
