MOSCOW (Reuters) - Russian President Vladimir Putin ratified friendship treaties with two Moscow-backed Ukrainian breakaway republics on Tuesday, the Kremlin said.

       Russia has said the step allows it to build military bases there, deploy troops, agree a joint defence posture and tighten economic integration. The move comes amid a crisis over a huge Russian military buildup near Ukraine that has fuelled fears of an invasion, which Moscow denies planning.

       (Reporting by Tom Balmforth; Editing by Peter Graff)