A US government plan to lease out millions of hectares of seabed near the Mariana Trench for deep sea exploration has drawn opposition from US territories in the Pacific, as the Trump administration remains locked in a race with China for control of critical ocean minerals.

On Tuesday, the Marine Mineral Administration (MMA), an agency under the US department of the interior, released a proposal to auction deep sea mining leases for 28m hectares (69m acres) of seafloor off the coast of the Northern Mariana Islands and Guam.

The leases ​would allow companies to ‌explore the seabed and potentially extract ‌deposits of critical minerals – known as polymetallic nodules – that could be used in batteries, electronics and defence technologies. Many environmental ​groups have ​opposed deep sea mining, arguing that more research is needed on its effects on marine ecosystems.

The Northern Mariana Islands is a self-governing commonwealth of the United States, while Guam is an unincorporated territory of the US.

The governor of the Northern Marianas, David Apatang, has said his government would approach the Trump administration’s proposal “with extreme caution”.

Apatang, while acknowledging the strategic importance of critical minerals, said it was necessary that “no activity, survey or otherwise, takes place without rigorous scientific baseline studies, complete transparency, and explicit protections for our marine resources”.

He said his administration would “thoroughly examine the proposed terms over the next 60 days to ensure that the ecological integrity of our waters and the long-term wellbeing of the [Northern Marianas] are fully safeguarded”.

The Guardian approached the Marine Mineral Administration for comment.

In an earlier statement, the MMA said it had completed an environmental review of proposed commercial leases for critical minerals in the Marianas area. The MMA said it would consider comments from the governor.

A statement from the office of the governor of Guam acknowledged the Trump administration’s focus on national security and strategic needs, but added: “National security cannot mean asking the people of the Pacific to accept environmental risks before those risks are fully understood.

“We’re unequivocally opposed to the deep sea mining efforts in this region,” said Guam’s lieutenant governor, Joshua Tenorio.

He told the Guardian: “The department of interior is giving assurances that mining activity is not going to commence with the awarding of these licences, [but] I think that this is a matter where we can’t really trust that because this has been rapidly evolving.”

The proposed lease notice for deep sea exploration in the Marianas region came just weeks after the initiation of a leasing process for 12.4m hectares (31m acres) of American Samoa’s seafloor, with plans to award contracts in November.

The governor of American Samoa, Nikolau Pula, said his government remained opposed to deep sea mining, noting that untested extraction processes could harm the territory’s tuna industry, which fuels its economy.

On 19 August, environmental groups in American Samoa and Hawaii launched legal proceedings against the US government to halt the proposed auction of seafloor permits around the islands, alleging that federal agencies failed to evaluate the destructive impact mineral extractions could have on marine ecosystems.

In a Hawaii court, Fa’asao Ameika Samoa and the Conservation Council for Hawaii warned that the extraction machinery “can destroy nearly all life in its path” and “stirs up sediments that can introduce toxic substances into the food web and smother seafloor ecosystems”.

“Even just exploring for seabed minerals introduces extremely loud noise into the marine environment that can harm marine mammals and other wildlife,” the complaint reads.

The Marine Mineral Administration was approached about the concerns over the American Samoa leasing process.