MOSCOW — Russia's lower house of parliament voted unanimously Wednesday to suspend participation in a key European arms control treaty, approving President Vladimir Putin's initiative in a show of defiance to the West.

In a 418-0 vote, the State Duma approved legislation calling for Moscow to temporarily abandon its obligations under the Conventional Forces in Europe treaty — a pact straining Russia's relations with the United States and Europe.

Approval in the Duma, which is dominated by the Kremlin-controlled United Russia party, was a a foregone conclusion. The legislation now goes to the upper house — where approval also is virtually certain — before it goes to Putin for his signature.

Under the moratorium, Russia would halt inspections and verifications of its military sites by NATO countries and would no longer limit the numbers of its conventional weapons, the Foreign Ministry said. It would take effect Dec. 12.

Putin first threatened to suspend participation in the treaty in April amid mounting Russian anger over U.S. efforts to build a missile defense system in eastern Europe and frustration with growing Western influence over ex-Soviet nations.

The 1990 arms control treaty set limits on the deployment of conventional armaments by NATO and Warsaw Pact countries. It was revised in 1999 after the collapse of the Soviet Union.

Russia ratified the updated treaty in 2004, but the United States and other NATO members have refused to follow suit, saying Moscow first must fulfill obligations to withdraw its forces from Georgia and Moldova's separatist region of Trans-Dniester.

Russia says the withdrawals are not a condition for ratification, and Putin complained in May that NATO countries are "filling eastern Europe with new weapons," forcing Moscow to take action out of security concerns.

Deputy Assistant Secretary of State David Kramer said last week that the United States and its allies disagree that Russia's security concerns are reason enough to suspend the treaty.

However, Russian legislators' move to suspend participation appears driven less by security concerns than by Moscow's desire to emphasize to the West that its interests cannot be ignored.

Konstantin Kosachev, head of the Duma's international affairs committee, said the suspension was "not an act of aggression" and was not aimed to scuttle the treaty, though Putin has said Russia could pull out altogether if its efforts bring no NATO response.

Analysts say Russia has no interest in a costly buildup of forces because it faces no real military threat from NATO and has no plans to launch an attack of its own.

NATO spokesman James Appathurai said the alliance would be worried by a military buildup in western Russia, saying that "to see large amounts of what is now treaty-limited equipment suddenly moving ... would be a concern to NATO countries."

Appathurai said NATO and its 26 members regretted the vote and are still seeking to convince Russia to change its mind.

"This treaty is very important for European security," he told reporters. "It's very important that Russia fulfills its obligations."