- Russia continues to boost its Arctic military presence, according to satellite photos obtained by CNN.
- The photos show improvements being made to Russian radar bases and runways, CNN reported.
- NATO's chief said Friday there is now "a significant Russian military build-up in the high north."
Russia is growing its military presence in the Arctic even while it struggles in Ukraine, according to NATO and satellite photos obtained by CNN.
The photos show improvements made over the past year to Russian radar bases and runways.
Satellite company Maxar Technologies, which took the photos, told CNN that the images show ongoing work on radar stations in two locations: Olenegorsk, in northwest Russia close to Finland; and Vorkuta, north of the Arctic circle.
Thye also appeared to show work to build a radar system at Ostrovnoy, which is close to Russia's borders with Finland and Norway in the northwest, Maxar said.
The company told CNN that works to add new equipment and protect old equipment had been completed at Tiksi, a site in the north, and there were runway improvements at two other bases.
NATO Secretary General Jens Stoltenberg told CNN on Friday that there is now "a significant Russian military build-up in the high north," and that NATO had decided to "double its presence" in the area in response to recent tensions.
He said those bases were still important to Russia, even as the country is focusing much of its resources on its invasion of Ukraine.
"The shortest way from Russia to North America is over the Arctic North Pole. So the strategic importance of these areas has not changed because of the war in Ukraine," he told CNN.
"We see Russia reopening old Soviet bases, military sites" he said, adding that the country is also "testing novel weapons in the Arctic and the high north."
As Insider's Christopher Woody previously reported, Russia has the world's longest Arctic coastline, and has spent years refurbishing military bases and deploying more troops in the region. Russia also maintains nuclear-capable ships there.
The Center for Strategic and International Studies think tank said last year that Russia is "re-militarizing the Arctic. Cold War-era bases are being restored, and new infrastructure is being built."
Stoltenberg told CNN that NATO had now doubled its presence in the Baltic and North Seas after explosions earlier this year damaged the Nord Steam pipelines.
He said NATO was increasing its presence "partly to monitor, to have better situational awareness, but also to send a message of deterrence and readiness to protect this critical infrastructure."