MOSCOW—President Vladimir Putin said Wednesday that Moscow would seek Western guarantees precluding any further NATO expansion and deployment of its weapons near his country’s borders, a stern demand that comes amid fears of a Russian invasion of Ukraine. Ukrainian and Western officials have worried about a Russian troop buildup near Ukraine, saying it could signal Moscow’s intention of an attack. Russian diplomats countered those claims by expressing concern about Ukraine’s own military buildup near the area of the separatist conflict in the eastern part of the country. Speaking at a Kremlin ceremony where he received credentials from foreign ambassadors, Putin emphasized that Russia will seek “reliable and long-term security guarantees.” “In a dialogue with the United States and its allies, we will insist on working out specific agreements that would exclude any further NATO moves eastward and the deployment of weapons systems that threaten us in close vicinity to Russian …