Vladimir Putin made a big deal of Russia’s success in seizing control of Kupyansk in eastern Ukraine late last year, even as Volodymyr Zelenskiy immediately challenged the claim by making a video address from the town.

MOSCOW, March 31 (Reuters) - Ukrainian drones on Tuesday struck Russia's Baltic Sea port of Ust-Luga for the fifth time in 10 days, and industry sources told Reuters an oil loading terminal was hit, likely adding to Russia's difficulties in exporting crude.