President Donald Trump has signed an executive order aimed at boosting the deep-sea mining industry, marking his latest attempt to boost US access to nickel, copper and other critical minerals used widely across the economy.

The order, which Trump signed in private, seeks to jumpstart the mining of both US and international waters as part of a push to offset China's sweeping control of the critical minerals industry.

Parts of the Pacific Ocean and elsewhere are estimated to contain large amounts of potato-shaped rocks known as polymetallic nodules filled with the building blocks for electric vehiclaes and electronics.

More than 1 billion metric tons of those nodules are estimated to be in US waters and filled with manganese, nickel, copper and other critical minerals, according to an administration official.

Extracting them could boost US GDP by $300 billion over 10 years and create 100,000 jobs, the official added.

"The United States has a core national security and economic interest in maintaining leadership in deep-sea science and technology and seabed mineral resources," Trump said in the order.

The order directs the administration to expedite mining permits under the Deep Seabed Hard Minerals Resource Act of 1980 and to establish a process for issuing permits along the US Outer Continental Shelf.

It also orders the expedited review of seabed mining permits "in areas beyond the national jurisdiction," a move likely to spark friction with the international community.

The International Seabed Authority - created by the United Nations Convention on the Law of the Sea, which the US has not ratified - has for years been considering standards for deep-sea mining in international waters, although it has yet to formalize them due to unresolved differences over acceptable levels of dust, noise and other factors from the practice.

Supporters of deep-sea mining say it would lessen the need for large mining operations on land, which are often unpopular with host communities. Environmental groups are calling for all activities to be banned, warning that industrial operations on the ocean floor could cause irreversible biodiversity loss.

"The United States government has no right to unilaterally allow an industry to destroy the common heritage of humankind, and rip up the deep sea for the profit of a few corporations," said Arlo Hemphill of Greenpeace, which opposes the practice.

Any country can allow deep-sea mining in its own territorial waters, roughly up to 200 nautical miles from shore, and companies are already lining up to mine US waters.

Impossible Metals earlier this month asked the administration to launch a commercial auction for access to deposits of nickel, cobalt and other critical minerals off the coast of American Samoa.