"Russia has generally followed international law and procedure in establishing the limits of its extended continental shelf. Russia could choose to unilaterally establish those limits if the procedures prove unfavourable and could utilize its military capabilities in an effort to deny access to disputed Arctic waters or resources", the report, released late on Thursday, said.
The Pentagon also suggested that the Arctic could be "a potential vector" for an attack on the United States.
"China and Russia pose discrete and different challenges in their respective theatres, but both are also pursuing activities and capabilities in the Arctic that may present risks to the [US] homeland", it added.
This is not the first time Washington has lashed out at Moscow over its exploration of the northernmost part of Earth. Despite this tension, Russia has repeatedly stressed that the Arctic is an area where Arctic Council member states — Canada, Denmark, Finland, Iceland, Norway, Russia, Sweden, and the United States — should work for constructive dialogue and conflict-free partnership.
The criticism of Russia's allegedly aggressive actions in the region has been accompanied by Washington increasing its military activity in the area. In late 2018, reports emerged that Washington was eyeing to reopen the Cold War-era Adak naval air base on the Aleutian Islands. The facility, situated in close proximity to Russia's north-eastern border, was operational between 1942 and 1997.