Russia must withdraw its troops from the Ukrainian border and enter into sincere dialogue with the West, NATO Secretary General Anders Fogh Rasmussen said on a visit to NATO-member Bulgaria on Friday.
NATO presented satellite photographs on Thursday it said showed Russian deployments of 40,000 troops near the Ukrainian frontier along with tanks, armoured vehicles, artillery and aircraft ready for action.
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Delivering much the same message that he has given on visits elsewhere, Rasmussen also said the NATO alliance was not discussing military action over Ukraine, but added that it was taking steps to protect its partners effectively.
A close Moscow ally during the Cold War, Bulgaria joined NATO 10 years ago and the European Union in 2007. Since the standoff between Russia and the West began over Ukraine, it has taken part in navy drills with an American warship in the Black Sea and hosted military exercises with U.S. troops on its soil.