Is Ukraine under threat of an imminent invasion by Russia?
One of Nato's top commanders thinks it is saying Russian forces gathering on the border with eastern Ukraine may be poised to invade.
Nato's supreme allied commander in Europe, General Philip Breedlove, says the Russian military force gathered near the border is "very, very sizeable and very, very ready" and could even pose a threat to Moldova, on the other side of the country.
Ukraine's Foreign Minister has also warned that the threat of war with Moscow is escalating.
However, Russia says it has complied with international agreements limiting the number of troops in the border areas with Ukraine.
Meanwhile, international monitors from the European security organization are set to arrive in Ukraine soon, but they will not go to Crimea.