WASHINGTON (Dispatches) -- Despite near gridlock in the Senate, Republicans were expected to swing behind a new arms control treaty with Russia and the U.S.

Barack Obama and Dmitry Medvedev signed an arms control treaty on Thursday that the White House hails as a big step forward in its bid to reset relations with Russia, as well as for the U.S. president’s broader nuclear agenda. The treaty requires approval by two-thirds of the U.S. Senate to take effect.
But prospects for ratification are uncertain for the strategic treaty, which cuts the number of long-range nuclear weapons each country can deploy by almost a third. 67 votes are needed for approval in the Senate, where the Democrats control 59 seats.
Republicans want Obama to promise it won’t undercut the nation’s ability to set up missile defenses to protect against an attack.
Republicans also want assurances that the agreement will preserve what’s known as “nuclear triad” – the nation’s ability to deliver nuclear weapons from the air, land and sea.
The treaty signed at a ceremony in a ballroom in Prague, the central European city where Obama laid out his vision of a nuclear-free world last year, reduces the number of strategic nuclear warheads each side can deploy to 1,550, along with cuts in launchers and new verification procedures.
The deal comes ahead of a critical sequence of meetings. Next week, Obama hosts a summit of more than 40 world leaders to improve controls on “loose” nuclear material.
The U.S. is also hoping the example set by the new START deal, a successor to the 1991 Strategic Arms Reduction Treaty, will encourage a United Nations conference in May to bolster the non-proliferation regime for states without nuclear weapons.
On Thursday, Obama said he expected the UN Security Council to agree “strong, tough sanctions on Iran this spring”. Washington says one of the most tangible results of the “reset” in U.S. relations with Moscow is Russia’s backing for another round of sanctions.
But Medvedev made clear the limits of Russian support when he said Moscow would only back “smart” sanctions.
“There’s no doubt that the present draft
[of UN sanctions] will be watered down,” said a senior European diplomat.