BRUSSELS - NATO Secretary-General Jens Stoltenberg said on Tuesday a "serious military buildup" was taking place both inside Ukraine and on the Russian side of the border. Information from NATO and other sources pointed to "a military buildup ... inside Ukraine. But we also see a military buildup on the Russian side of the border," he said.

"We call on Russia to pull back its troops and contribute to a peaceful agreement," Stoltenberg told reporters as he arrived for a meeting with European Union defense ministers in Brussels.

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— Reuters