U.S. President Barack Obama has urged the Senate to ratify the new START arms control agreement with Russia before the end of this year's congressional term.
Obama's Democratic Party saw its majority in the Senate trimmed after midterm elections on November 2.
The brief post-election legislative session is known as the 'lame-duck' session because it includes lawmakers who lost their re-election bid in the ballot.
Obama called the treaty "an issue of American national security."
The Russian Duma has also yet to ratify the treaty, which was signed by Obama and Russian President Dmitry Medvedev in April.
compiled from agency reports