(CNN) - Senate leaders disagreed Sunday over if and when to ratify a new arms control treaty with Russia.
Republican Arizona Sen. Jon Kyl said Congress has more urgent business to address than the New START (Strategic Arms Reduction Treaty) when they continue the lame-duck session this week.
Kyl said the treaty is complex and should wait until the Senate reconvenes in January.
Democratic Illinois Sen. Dick Durbin, however, said the Senate should debate the treaty in a responsible way before the winter break.
"To ignore and push aside the START treaty at this moment does not help our relationship with Russia in this critical issue of an Iranian nuclear program," Durbin said Sunday on NBC's "Meet the Press."
Meanwhile, Sen. Claire McCaskill, D-Missouri, blamed politics for the back and forth.
"There's some game-playing going on with the START treaty," McCaskill said on "Fox News Sunday." "It's all about politics and it's all about trying to damage the president of the United States."
The Obama administration has consistently pushed for passage of the treaty before the next congressional recess. Previously, Obama said failure to ratify the treaty would be a "dangerous gamble with America's national security."
START is a nuclear arms reduction agreement between Russia and the United States that allows inspectors on the ground in both countries to monitor nuclear activity. Although it has been signed by the leaders of both nations, Congress has failed to ratify the accord.
Congress returns to Washington on Monday and is expected to address the repeal of the "don't ask, don't tell" military policy, the extension of the Bush-era tax cuts and unemployment benefits.
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