Ukraine’s military demanded that pro-Russian rebels surrender and dismissed their offer of a cease-fire as lawmakers prepared to consider sanctions that may curb Russian shipments of natural gas to Europe . “If there’s an initiative, it should be implemented by practical means, not only with words — by raising white flags and putting down weapons,” Andriy Lysenko, a spokesman for the country’s military, told reporters yesterday in Kiev. “In that case, no one will shoot at them.” Ukraine is trying to dislodge thousands of separatists from its easternmost regions, where its U.S and European allies say President Vladimir Putin has been stoking deadly unrest for months. Russia , which denies involvement, wants its neighbor’s military campaign to end and is offering assistance to tackle what it describes as a worsening humanitarian disaster. As ties between the former Soviet allies sour further, lawmakers in Kiev will vote tomorrow on a […]