Obama praised the strong bipartisan vote for a treaty he described as the most significant arms control pact in nearly two decades.
“This treaty will enhance our leadership to stop the spread of nuclear weapons and seek the peace of a world without them,’’ he told reporters at a White House news conference.
The accord, which still must be approved by Russia, would restart onsite weapons inspections, as successors to President Reagan have embraced his edict of “trust, but verify.’’ Sergey Lavrov, the Russian foreign minister, said Moscow welcomed the vote but still needed to study the accompanying Senate resolution.
Vice President Joe Biden presided over the Senate and announced the vote. Secretary of State Hillary Rodham Clinton observed the vote from the Senate floor. Both former senators had lobbied furiously for the treaty’s approval.
“The question is whether we move the world a little out of the dark shadow of nuclear nightmare,’’ Foreign Relations Committee chairman John Kerry, a Massachusetts Democrat, said to his colleagues moments before the historic tally.
Calling the treaty a national security imperative, Obama had pressed for its approval before a new Congress with more Republicans assumes power in January. In recent days, he had telephoned a handful of wavering Republicans, eventually locking in their votes.
The Obama administration has argued that the United States must show credibility in its improved relations with its former Cold War foe, and the treaty was critical to any rapprochement. The White House is counting on Russia to help pressure Iran over its nuclear ambitions.
“A responsible partnership between the world’s two largest nuclear powers that limits our nuclear arsenals while maintaining strategic stability is imperative to promoting global security,’’ Clinton said in a statement applauding the vote.
Senate majority leader Harry Reid, Democrat of Nevada, said the vote bolstered Obama’s standing on the world stage.
“That treaty was the standing of the United States in the world community, and whether Barack Obama was a man who deserved the Nobel Peace Prize, a man who has so turned around American foreign policy,’’ Reid told the Associated Press in an interview.
