White House aides say the initiative could see US operations scoop up more than a billion metric tons of mineral-rich deep-sea nodules, and pump hundreds of billions of dollars into the American economy.

But the move to disrupt ocean floor ecosystems to extract cobalt and other minerals flies in the face of environmental group concerns and the controls set by global regulators at the International Seabed Authority. 

Since the 1990s, the group has sought to set ground rules for the burgeoning industry's extraction efforts in international waters. 

But the US never ratified the agreements that empowered the ISA's jurisdiction and is not a member of the UN-affiliated body. 

Instead, the Trump administration is "relying on an obscure 1980 law that empowers the federal government to issue seabed mining permits in international waters," the New York Times reported. 

ISA didn't immediately respond to AFP's request for comment.

Under the order, the secretary of commerce has 60 days to "expedite the process for reviewing and issuing seabed mineral exploration licenses and commercial recovery permits in areas beyond national jurisdiction."

- 'Environmental disaster' -

Commercial deep-sea mining remains in its infancy, but with a global race underway for rare earth minerals -- and the industry dominated by China -- Washington appears set on expanding its collection capacity to benefit its defense, advanced manufacturing and energy industries.

But environmental groups warn the process can cause major ecological damage.

"Fast-tracking deep-sea mining is an environmental disaster in the making," Emily Jeffers, a senior attorney at the Center for Biological Diversity, said in a statement.

"Trump is trying to open one of Earth's most fragile and least understood ecosystems to reckless industrial exploitation."

The boosted deep-sea mining policy is aimed in part at "strengthening partnerships with allies and industry to counter China's growing influence over seabed mineral resources," the White House said.

The ISA is scrambling to devise a rulebook for deep-sea mining, balancing its economic potential against warnings of irreversible environmental damage.

Last week the American firm Impossible Metals said it had asked US officials to "commence a leasing process" in a parcel of the Pacific Ocean surrounding far-flung US territory American Samoa.  

The bid circumvents the ISA by mining within US jurisdiction, rather than international waters.

Key seabed resources include polymetallic nodules, potato-sized pebbles found at depths of 13,000 to 20,000 feet (4,000 to 6,000 meters) that contain manganese, iron, cobalt, copper and nickel.

A senior administration official told reporters shortly before the signing that the US could retrieve more than a billion metric tons of material, and the process could create some 100,000 jobs and generate $300 billion in domestic GDP over 10 years.

Canada-based deep-sea mining frontrunner The Metals Company recently stunned industry observers with an attempt to sideline the ISA.

After years of pushing the authority to adopt rules for industrial-scale mining, The Metals Company abruptly announced earlier this year it would seek US approval instead, with CEO Gerard Barron lauding Trump's order.

"By building on decades of domestic innovation and regulatory groundwork, this action reasserts America's role in securing critical seabed resources and ensures the US is not left behind in a strategic arena increasingly influenced by China," Barron said in a statement.