The United States on Friday warned it would impose sanctions and other punitive measures against any nation supporting a proposed carbon tax on maritime transport being considered by a UN agency.

In a joint statement, Secretary of State Marco Rubio, along with the secretaries of energy and transportation, said Washington would “vigorously defend its economic interests by imposing costs on countries that back” the Net Zero Framework (NZF) a plan designed to curb global carbon emissions in the shipping industry.

The London-based International Maritime Organization (IMO) is scheduled to vote next week on adopting the NZF, which would introduce a global carbon pricing mechanism for the shipping sector.

The US government, however, slammed the proposal, calling it “a global carbon tax that would harm economic growth and penalize developing nations.”

Since retaking office in January, President Donald Trump has rolled back several climate initiatives, dismissing climate change as a “hoax” and promoting fossil fuel expansion through deregulation.

Rubio, Energy Secretary Chris Wright, and Transportation Secretary Sean Duffy reiterated that the Trump administration “categorically rejects” the NZF proposal and will resist any attempt to impose what it considers “globalist economic controls” through the UN framework.

They threatened a range of punishing actions against countries that vote in favor of the framework, including: visa restrictions; blocking vessels registered in those countries from US ports; imposing commercial penalties; and considering sanctions on officials.

“The United States will be moving to levy these remedies against nations that sponsor this European-led neocolonial export of global climate regulations,” the statement said.