MOSCOW -- Russia's landmark nuclear arms deal with the United States cleared its final hurdle Wednesday, winning overwhelming support from the upper house of parliament and opening the way for big cuts in both nations' nuclear arsenals.
The Federation Council ratified the accord, known as the Treaty of Moscow, in a 140-5 vote with two abstentions in a meeting held behind closed doors.
The vote was considered a mere formality, coming after the State Duma, the lower house of parliament, ratified the treaty earlier this month and the U.S. Senate approved it in March, but its timing -- days ahead of the Russia-U.S. presidential summit -- was significant.
President Vladimir Putin and President Bush are expected to exchange ratification documents in St. Petersburg on Sunday, bringing the accord into immediate force.
"This document meets Russia's national security interests and broadens the opportunity of cooperation with the U.S. and other countries on security issues," Foreign Minister Igor Ivanov said on state-controlled television.
Putin, who negotiated the treaty with Bush last year, lobbied hard for its ratification, which became temporarily threatened by Russian anger over the U.S. war in Iraq.
The Duma delayed an earlier scheduled vote that would have coincided with the start of the U.S. invasion. But after intense Kremlin lobbying, lawmakers put the accord back on the agenda this month.
Ivanov attended the Federation Council's closed-door session Wednesday to make a final pre-vote plea for ratification.
The accord calls on Russia and the United States to cut their strategic nuclear arsenals by about two-thirds, to 1,700 to 2,200 warheads, by 2012.
The treaty's supporters say it will allow Russia to retain its Soviet-built missiles equipped with multiple nuclear warheads, which form the core of the nation's nuclear arsenals and were to be scrapped under the earlier START II arms reduction treaty. Russia never ratified that accord.
They also note that Moscow would have had to decommission many of its aging nuclear missiles anyway.
Opponents note the treaty allows each country to stockpile the warheads, which are to be taken off-duty, contrary to Russia's initial push for their destruction. The cash-strapped Russian military cannot afford to maintain nuclear arsenals on a par with the United States.
Mikhail Margelov, chairman of the foreign affairs committee of the Federation Council, was quoted by the Interfax news agency as saying that the treaty fills "a legal vacuum in the sphere of strategic stability" left by Washington's decision to withdrawal last year from the 1972 Anti-Ballistic Missile Treaty in order to deploy a national missile defense shield.
Moscow and Washington's carefully constructed friendship came under strain with the Iraqi war, which Russia strongly opposed.
The Kremlin has since made an effort to mend the rift, with observers noting that this treaty's ratification will likely be used to send a sign that the relationship is moving beyond the Iraqi disagreement.
"In fact, there are many issues that play a much bigger role than Iraq," said Sergei Rogov, director of Russia's USA and Canada Institute, citing the arms treaty as an example.