Adds details from executive order throughout, reaction from environmental group in paragraph 12

By Ernest Scheyder and Jarrett Renshaw

April 24 (Reuters) - President Donald Trump on Thursday signed an executive order aimed at boosting the deep-sea mining industry, marking his latest attempt to boost U.S. 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 U.S. and international waters as part of a push to offset China's sweeping control of the critical minerals industry.

Reuters first reported last month that the order was under deliberation.

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 vehicles and electronics.

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

Extracting them could boost U.S. 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 U.S. 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 U.S. 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 deep ocean belongs to everyone and protecting it is humanity's global duty. The sea floor environment is not a platform for 'America First' extraction," said Emily Jeffers of the Center for Biological Diversity, a conservation group that 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 U.S. 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.

Shares of The Metals Company TMC.O - among the most prominent of deep-sea mining companies - rose on Thursday by roughly 40% to hit a 52-week high of $3.39 per share after the Reuters report earlier in the day on the executive order.

Beyond The Metals Company, others eyeing deep-sea mining include California-based Impossible Metals, Russia's JSC Yuzhmorgeologiya, Blue Minerals Jamaica, China Minmetals, and Kiribati's Marawa Research and Exploration.

OTHER MINING STEPS

U.S. access to critical minerals - especially those produced by Chinese companies - has dwindled in recent months as Beijing has limited exports of several types. That, in turn, has ratcheted up pressure on Washington to support efforts to boost domestic mining.

Last week, Trump officials fast-tracked permitting on 10 mining projects across the United States and implemented an abbreviated approval process for mining projects on federal lands.

The administration also said it would approve one of the country's largest copper mines.

Trump's Thursday order uses the term "rare earths" to broadly refer to all critical minerals and is not meant to imply the administration believes the nodules contain neodymium and the 16 other rare earths, the administration official said.

(Reporting by Jarrett Renshaw and Ernest Scheyder; Editing by Aidan Lewis and Daniel Wallis)

((jarrett.renshaw@thomsonreuters.com; (646) 223-6193;))