U.S. President George W. Bush's national security adviser says the leaders of the U.S. and Russia can leave the missile defense issue to their successors after failing to reach agreement in their last meeting together as Presidents. Stephen Hadley made the comments aboard Air Force One following farewell talks Sunday in Russia between Bush and President Vladimir Putin, who leaves office on May 7. Asked whether he expects the U.S. and Russia to achieve a missile defense agreement before Bush leaves office in January, Hadley said: «They can leave that to their prospective successors.» The White House says Bush will soon be dealing with Russian President-election Dmitry Medvedev, although Hadley suggested that Putin would likely stay involved on missile defense and other foreign policy matters. He says «that seems to be a good thing, not a bad thing.»