Both houses of Russia’s parliament ratified the START nuclear arms reduction treaty.
The upper house Federation Council ratified the treaty on Wednesday, a day after the Duma, the lower house.
The U.S. Senate ratified the treaty in December, overcoming resistance from a faction within the Republican Party that said its terms were too loosely defined.
The Obama administration solicited backing from Jewish groups for passage, saying it was critical to getting Russia’s cooperation in isolating Iran.
The pact will reduce arsenals by about 30 percent.