Russia on Thursday welcomed the US Senate's approval of a treaty slashing the nuclear missile arsenals of the Cold War foes, with parliament saying it could ratify the accord as early as this week.
US senators ratified Wednesday the new Strategic Arms Reduction Treaty (START) after a months-long political battle, putting the ball firmly in the court of the Russian legislature to respond.
President Dmitry Medvedev, who signed the treaty in Prague in April with his US counterpart Barack Obama, welcomed the US lawmakers' ratification "with satisfaction", his spokeswoman Natalya Timakova said in a statement.
START restricts the former Cold War foes to a maximum of 1,550 deployed warheads each, a cut of about 30 % from a limit set in 2002, and 800 launchers and bombers.
In Russia, the treaty still requires approval from the State Duma (lower house of parliament) and the Federation Council (upper house). Top lawmakers had long emphasised they would only consider the issue after the US approval.
Timakova said Medvedev "expressed hope that the State Duma and Federation Council are ready to examine this question and ratify the document."
With the Duma dominated by the pro-Kremlin United Russia party which usually fulfills Medvedev's orders with not so much as a query, observers expect Russia to ratify the agreement with none of the squabbles seen in the United States.
The main question is the speed at which the process will take place, observers say.
Duma speaker Boris Gryzlov said the parliament needed to examine the final document agreed by the US Senate -- which was amended from the initial draft -- and it was still awaiting a copy of the original text to examine.
But he added: "If the conditions (in the US Senate resolution) do not affect the basic text of the agreement then we could adopt the treaty on Friday."
Sergei Mironov, speaker of the Federation Council, said that his lawmakers could also pass the document on Friday if the Duma passes it then, Russian news agencies reported.
"Space has been made for discussing this question on Friday although it has not yet been added to the agenda," the ITAR-TASS news agency quoted him as saying.
However the Duma council of its top lawmakers cancelled without explanation a meeting planned for 1300 GMT on Thursday that was due to discuss the date of the ratification, Russian news agencies said.
The new START nuclear arms control treaty is a centrepiece of the US-Russia drive spearheaded by Medvedev and Obama to "reset" relations and the delay in ratification has risked turning into a diplomatic embarrassment.
Prior to approving the treaty, US lawmakers attached non-binding amendments to the resolution to recommit Washington to deploying a missile defence system, to modernising its nuclear arsenal, and to seeking new talks with Russia on curbing tactical nuclear weapons.
Russia had warned against attempts by US lawmakers to amend the treaty, with Foreign Minister Sergei Lavrov this week bluntly stating that it "cannot be reopened".
Speaking to reporters on Thursday, Lavrov declined to comment on the US amendments to the treaty, saying Russia needed to see the final document first.
Foreign Secretary William Hague of Britain, a fellow nuclear power, described the treaty as "an important step towards our long-term goal of a world without nuclear weapons" and called on Russia to ratify it as soon as possible.
Two minority factions -- the ultra-nationalist Liberal Democratic party and the Communists -- said they would vote against ratification. But with United Russia holding 314 seats in the 450 seat chamber, their objections are of mere ceremonial importance.
"Our faction will not vote for it because we believe that we have to seriously approach the issue concerning the country's security," Interfax quoted Gennady Zyuganov, the long-serving Communist leader, as saying.