Senate Majority Leader Harry Reid, D-Nev., issued a statement Wednesday supporting quick action on the treaty, saying he was "puzzled" by Kyl's stance.
But the administration's hopes suffered another hit when Republican Sen. George Voinovich, an Ohio moderate who is retiring this year, expressed his reservations about the treaty.
"America's grand strategy approach towards Russia must be realistic, it must be agile, and as I have said it must take into account the interests of our NATO allies," Voinovich said in a statement. "I am deeply concerned the New START Treaty may once again undermine the confidence of our friends and allies in Central and Eastern Europe."
A clearly frustrated Lugar, the top Republican on the Senate Foreign Relations Committee and a treaty supporter, suggested the administration press ahead with a vote despite the opposition of Kyl and others. Lugar, a leading voice on nuclear issues, said if the White House and Democrats wait until next year and the new Congress, the process would have to start anew with hearings, committee votes and a greater risk that the treaty won't be ratified.
"This is a situation of some national security peril," Lugar told reporters.
Obama and Russian President Dmitry Medvedev signed the pact in Prague in April. Obama met with Medvedev last weekend on the sidelines of an economic meeting in Japan and emphasized his commitment to advancing the treaty during the lame-duck session.
The treaty would reduce U.S. and Russian strategic warheads to 1,550 for each country from the current ceiling of 2,200. It also would set up new procedures to allow both countries to inspect each other's arsenals to verify compliance.
Kerry said there were no substantive disagreements on the treaty itself and that a major objection of Kyl's should have been removed when the administration pledged an additional $4.1 billion for weapons modernization programs.
Republicans have argued that the treaty would limit U.S. missile defense options and does not provide adequate procedures to verify that Russia is living up to its terms.
AP White House Correspondent Ben Feller contributed to this story.
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