Russian and Ukrainian officials on Sunday continued a series of measured steps aimed at decreasing tensions before the countries’ presidents meet this week to discuss the six-month conflict in Ukraine ’s east. Despite the continuing fighting over disputed territories, President Petro O. Poroshenko of Ukraine said he believed that a full cease-fire could soon be achieved under a peace plan that he and Russia ’s president, Vladimir V. Putin , had endorsed. On Sunday, Russian news agencies reported that Mr. Putin had ordered troops deployed on the Ukrainian border to return to their bases. It was the second time this year that Mr. Putin had announced that military exercises along the Ukrainian border had been completed and that 17,600 soldiers would be withdrawn to their usual bases. Mr. Putin ordered the pullback from the Rostov region, which borders Ukraine, in a meeting with his defense minister, […]