The White House says the Obama administration's "reset" of relations with Russia will continue if Vladimir Putin returns to the presidency.
National Security Council spokesman Tommy Vietor said Saturday that "the reset has always been about national interests and not individual personalities."
Putin was sometimes harshly critical of the United States and relations with the U.S. eroded during his second presidential term. President Dmitry Medvedev, elected in 2008, was Putin's protege and hand-picked successor but cultivated a more pro-Western image.
President Barack Obama made restoring ties with Russia a priority. Medvedev signed the New START treaty with the U.S. limiting nuclear arsenals, opened Russian routes for U.S. supplies to Afghanistan and agreed to toughen UN sanctions against Iran.
Prime Minister Putin remained Russia's most powerful political figure during Medvedev's single term in office. Medvedev is expected to become Putin's prime minister after the March election.