Backers of the regulation said the framework’s implementation would provide alignment on emissions and strengthen investment signals for new fuels and technologies.

This comes after the IMO postponed an October 2025 vote on the framework, which was widely expected to unlock demand for green hydrogen-based fuels like ammonia and e-methanol.

57 countries voted in favour of the delay, 49 opposed, and 21 abstained.

First approved in draft form in April 2025, it would impose a carbon levy on ships above 5,000 tonnes from 2028.

The call to action said the net-zero framework represents a “hard-fought compromise” needed to accelerate Net Zero, and to provide clarity around new fuels, vessels and infrastructure.

After the 12-month postponement, IMO member states will vote on the framework later this year after the push by its backers, which include hydrogen players such as Moeve, Nel, Yara International, and Thyssenkrupp Nucera, among others.

“Confusion and uncertainty resulting from delay in the adoption of the Framework risks undermining international investment and growth in the solutions needed to enable shipping’s energy transition,” said the signatories in a statement on March 4.

Hydrogen and ammonia firms stand to benefit from the framework, which has already underpinned early momentum for green hydrogen-based fuels in maritime.