Updated

Senior military officers of the North Atlantic Treaty Organization described Russian military forces deployed in more than 100 makeshift bases just across the border with Ukraine as being in a state of high readiness—able to move swiftly within hours of a command from the highest level.

In a briefing to reporters at the alliance's military headquarters in southern Belgium that officials said was aimed at countering "misperceptions" promoted by Russia, NATO officers showed satellite images of fast aircraft, tanks, armored vehicles, artillery and temporary bases of troops it assessed to be airborne or special forces.

"I would assess that this is a force that is very capable at high readiness, and…is close to routes and line of communications and has the resources to move into Ukraine if it was ordered to do so…It's parked, it's stopped. but it can move very quickly," said Brigadier Gary Deakin, a U.K. army officer who heads NATO's crisis-operations center.

"Threat is capability and intent…Undoubtedly, there is capability here. We are unsure of the Russian intent," he said. He said NATO saw no direct threat from Russia at this time.

He added NATO assessed that troops would be capable of moving within 12 hours of an order coming from the highest level.

Officers said the military buildup had taken place since early-March following Russia's invasion of Crimea, but said there was no evidence of military exercises taking place—an explanation used by Moscow for the troop movements.

Asked if the deployments could be used for exercises, Brigadier Deakin said: "Potentially, they could be used for exercising…[But] it's quite unusual to have so much stuff there."

There had been little change in the forces deployed in recent weeks, he said. He said he had no indications of Russian aircraft overflying Ukraine.

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