MOSCOW: President Dmitry Medvedev says Russian armed forces must prepare to counter US missile defense plans.

Medvedev said Tuesday that even though diplomatic efforts are continuing, Russia must be ready to mount a military response to the US-led Nato missile shield.

He was quoted by Russian news agencies as saying that Russia should be ready to take retaliatory measures by 2017-2018.

Nato has said it wants to cooperate with Russia on the missile shield intended to fend off the Iranian missile threat, but it has rejected Russia's proposal to run the shield jointly.

Without a Nato-Russia cooperation deal, Medvedev has sought guarantees from the US that any future missile defense is not aimed at Russia.

He has threatened to aim missiles at the US shield if no agreement is reached.