The Pentagon says it is watching Russia's military activities in the Arctic "very closely" as signs mount of Moscow's ongoing efforts to boost its presence in and around its northernmost territories.
The statement by the U.S. military comes amid reports of advanced weapons tests and satellite imagery showing continued buildup of bases, storage, and equipment on Russia's Arctic coastline.
"Without getting into specific intelligence assessments, obviously we're monitoring it very closely," Pentagon spokesman John Kirby told a briefing on April 5. "Nobody's interested in seeing the Arctic become militarized."
Rapid melting in the Arctic brought on by climate change has opened increased shipping and resource-exploitation opportunities in polar regions, intensifying a race to project power and defend national interests by coastal and other powers.
The region is also thought to be home to enormous oil and gas deposits.
Russia's navy used nuclear-powered submarines to break through thick Arctic ice late last month in an apparent display of power in the Far North.
Washington has also cited the refurbishment of Soviet-era installations, new port construction, search-and-rescue centers, and a fleet of new icebreakers that includes nuclear-powered craft.
Kirby noted that the region "is key terrain that's vital to our own homeland defense and as a potential strategic corridor between the Indo-Pacific, Europe, and the [United States]."
"We're committed to protecting our U.S. national-security interests in the Arctic by upholding a rules-based order in the region, particularly through our network of Arctic allies and partners."
Washington last year boosted aid to Greenland to strengthen military ties in the Arctic region, after a public offer floated by then-President Donald Trump to buy that vast autonomous Arctic island angered Denmark.
China describes itself as a "near Arctic state" as it, too, tries to lay the foundations for greater shipping and mining activities in the region.