The trip comes as both countries are entering the process of power shifts, with Putin preparing to hand over his post to his chosen successor, Dmitry Medvedev, and two major US political parties are locked in fiercer campaign before the November presidential race.

Moscow has so far refused to give in over the issue. Last month, Putin said at his annual press conference that Russia has "to take countermeasures... and target those which we think will a pose threat to us." Medvedev has pledged to continue Putin's set policies when he takes office.

The Bush administration seems to stop at nothing in its attempt to expand the missile shield to Russia's backyard. The White House hopefuls of the two parties, including Democrats Barack Obama, Hillary Clinton and Republican John McCain, all voiced support for the planned US missile shield in Central Europe.

With views on the missile shield widely apart, Rice and Gates are expected to have some hard bargaining to do during their Moscow visit. As both sides consider the issue involves their key strategic interests, the debate on the issue may well be passed on to their future leaders, analysts noted.

(Xinhua News Agency March 14, 2008)