NATO is increasingly concerned about China’s shipping on Russia’s Northern Sea route, and the possibility that its commercial and scientific interests could be a precursor to a Chinese military presence in the Arctic, the alliance’s senior military officer said.

"We know there are military scientists on board these ships,” Admiral Rob Bauer, who chairs NATO’s Military Committee, said in an interview in Iceland on Saturday. "They haven’t said they won’t go there militarily.”

NATO is concerned about China’s aims given its increasingly close ties with Russia, including cooperation on energy and transportation that have caused a surge in Russian crude shipments to China through Arctic waters.