WASHINGTON - Despite skepticism from Republican opponents who worry that the United States is deliberately fraying its nuclear advantage, the Obama administration considers a new arms-control pact with Russia a disarmament bargain.

The agreement is more important for the diplomatic bargain it seals with a restive Russia than the limits it places on weapons that neither side was likely to use - treaty or no treaty.

It will probably also help cinch Russian cooperation with an American plan to protect Europe with an anti-missile shield arrayed against Iran.

Presidents Barack Obama and Dmitry Medvedev congratulated each other by phone Thursday, the White House said. The two leaders called the agreement historic and the capstone for a "very productive year" of cooperation on issues including Iran sanctions and the war in Afghanistan.

Medvedev already had welcomed the U.S. Senate's decision to ratify the landmark nuclear arms-control treaty, while Russian legislators said they need to study a resolution accompanying the document before following suit.

The Senate voted 71-26 on Wednesday to ratify the treaty, a clear victory for the White House after weeks in which it seemed doubtful that President Barack Obama could muster enough Republican votes.

The pact, called New START, is the centerpiece of a mutual U.S.-Russian effort to repair relations badly damaged during the latter years of the George W. Bush administration.

With Bloomberg News

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