SOCHI, Russia (Reuters) - A US ballistic missile defence site which has entered service in Europe threatens global security and is a step to a new arms race, Russian President Vladimir Putin said on Friday (May 13), vowing to adjust budget spending to neutralise its threats to Russia.

The United States switched on an US$800 million (S$1.1 billion) missile shield in Romania on Thursday that it sees as vital to defend itself and Europe from so-called rogue states but the Kremlin says is aimed at blunting its own nuclear arsenal.