SOCHI, Russia (Reuters) - The expansion of the United States' ballistic missile defence system is a threat to Russia's nuclear capability, Russian President Vladimir Putin said on Thursday.
Putin added that U.S. ballistic missile shield bases in Eastern Europe could also be used to station offensive weapons and that he was worried about NATO military infrastructure moving closer to Russia's borders.
(Reporting by Denis Dyomkin; Writing by Polina Devitt and Alexander Winning; Editing by Christian Lowe)
