MOSCOW — A key member of Russia’s parliament says he expects Russia to ratify a U.S.-Russia arms treaty by the end of the month.

Russia’s lower house of parliament gave preliminary approval to the treaty before the New Year’s holidays, but decided to delay a final vote to give the Russian side time to study the resolution passed by the Senate when it ratified the pact last month.

Konstantin Kosachyov, who heads the State Duma’s foreign affairs committee, told AP Television News on Friday they are now ready to ratify the treaty. He said Russia will introduce its own amendments to the ratification document “to balance the work that has been done by the Senate.”

The New START treaty limits each country to 1,550 strategic nuclear warheads, down from the current ceiling of 2,200.