Kharkiv counteroffensive is ‘unstoppable’: Ukrainian official The withdrawal of Russian forces from Ukraine’s second-largest city and the region around it “can not be stopped,” a Ukrainian official says. “This counterattack of ours can’t be stopped, and the Russians feel it. That’s why they sometimes retreat chaotically, blowing up bridges to stop the counteroffensive,” Interior Ministry advisor Vadim Denysenko said in televised remarks. Reporting by Mansur Mirovalev in Kyiv.