A senior Russian lawmaker says the lower house of parliament will not be able to give its full approval to a U.S.-Russian nuclear arms treaty until at least next month, as AP reported. Konstantin Kosachev, the head of the State Duma's foreign affairs committee, says that the legislators on Friday will only pass the ratification bill in the first of three required readings. Kosachev said the Russian parliament would need more time to study the Senate legislation accompanying the treaty. Russia's President Dmitry Medvedev has congratulated U.S. President Barack Obama on the Senate's approval of the treaty, which the two leaders hailed as a historic event.