The US on Tuesday rejected the “Net-Zero Framework” proposal by the International Maritime Organisation, which is aimed at reducing global greenhouse gas emissions from the international shipping sector, and threatened measures against countries that support it.

The announcement was made in a joint statement by Secretary of State Marco Rubio, Commerce Secretary Howard Lutnick, Energy Secretary Chris Wright and Transportation Secretary Sean Duffy, comes ahead of a vote at the United Nations’ shipping agency to adopt the net-zero proposal in October.

“The Trump Administration unequivocally rejects this proposal before the IMO and will not tolerate any action that increases costs for our citizens, energy providers, shipping companies and their customers, or tourists,” the statement said.

“Our fellow IMO members should be on notice that we will look for their support against this action and not hesitate to retaliate or explore remedies for our citizens should this endeavor fail,” it continued.

The US already exited IMO talks on the net-zero framework in April and urged other IMO members in a memo seen by Reuters to reconsider their support for it.

The World Shipping Council, which represents major shipping firms like container carrier Maersk and car carrier Major global container shipping companies, including Maersk and car carrier Wallenius Wilhelmsen, declined comment.

Many WSC members already have committed to net zero operations by 2050.

President Donald Trump has also said he is withdrawing the United States from the Paris climate agreement, which set a goal for countries to achieve net-zero emissions by 2050.

The US is currently engaging in UN negotiations to secure a global treaty to reduce plastic pollution and has warned countries in a memo that it will not support a pact that sets caps on plastic pollution and bans the use of certain chemicals.

Shipping, which transports around 90% of world trade and accounts for nearly 3 per cent of the world’s carbon dioxide emissions, has faced calls from environmentalists and investors to deliver more concrete action, including a carbon levy.

The United States is one of 176 IMO member states.