Russian forces seized full control of the eastern Ukrainian city of Sievierodonetsk on Saturday, both sides said, confirming Kyiv’s biggest battlefield setback for more than a month following weeks of some of the war’s bloodiest fighting.
Ukraine called its retreat from the city a “tactical withdrawal” to fight from higher ground in Lysychansk on the opposite bank of the Siverskyi Donets river. Pro-Russian separatists said Moscow’s forces were now attacking Lysychansk.
The…