A long-simmering conflict in eastern Ukraine is escalating into a flashpoint for superpower rivalry, as a Russian military build-up is met by the deployment of two American warships to the Black Sea. Putin has ordered the largest movement of troops, tanks and missiles along the Ukrainian border since the Crimea 2014 invasion. About 85,000 troops, tanks, missile trucks, armoured vehicles and long-range guns are being transported by train to Crimea and strategic locations near the disputed region. Amongst the armoury are anti-aircraft missile systems last used in 2014 to destroy a civilian Boeing 777 over Ukraine, killing 298 people. Many fear Moscow is on the point of a full-scale invasion, and see the Ukrainian authorities preparing for this possibility. Putin's deputy chief of staff said Ukraine faced 'disintegration' if it pushed Russia into war. Meanwhile Washington is flying reconnaissance planes to monitor Russian activity. See also