The lower house of the Russian parliament, the Duma, has voted to give initial approval to the Start nuclear arms pact with the US.
The treaty, aimed at reducing both countries’ nuclear arsenals and allowing their inspection, was ratified by the US Senate on Wednesday.
There were hopes the Duma would give its full approval but officials decided that two more readings were necessary.
The pact must also be ratified by the upper house, the Federation Council.
Before MPs voted to back the treaty by 350 votes to 58, concerns were expressed in the Russian parliament about two non-binding amendments that had been made by the Senate before ratification.
Russian Foreign Minister Sergei Lavrov said the amendments – committing the US to a missile defence system and modernising its nuclear arsenal – did not change the treaty as a whole.
He said it was “unacceptable” that the US was trying to ensure that “future strategic-range non-nuclear systems” not currently covered by the pact should not be subject to its terms.
Earlier, Russian President Dmitry Medvedev praised President Barack Obama for pushing the pact through the Senate.
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