By Jonathan Landay and Tom Balmforth RUSKA LOZOVA, Ukraine (Reuters) – Russia pummelled positions in the east of Ukraine on Sunday, its defence ministry said, as it sought to encircle Ukrainian forces in the battle for Donbas and fend off a counteroffensive around the strategic Russian-controlled city of Izium. At a meeting in Germany, the secretary-general of the North Atlantic Treaty Organization (NATO) said Ukraine could win the war, calling for more military support and fast-track approval of expected bids by Finland and Sweden to join the alliance. Ukraine has scored a series of successes…