Russia's UN envoy has warned that Moscow might not sign the first treaty on the global arms trade after it was overwhelmingly approved by the UN General Assembly.
Russia, the world's second-largest arms supplier with an estimated $8 billion in sales last year, abstained in Tuesday's vote.
The final vote tally for the treaty meant to regulate the $70 billion business in conventional arms and keep weapons out of the hands of human rights abusers was 154 in favor, three against and 23 abstained.
Russia's ambassador to the United Nations, Vitaly Churkin, complained that the draft treaty lacked a clause banning the supply of weapons to non-state entities.
"Despite persistent appeals from many states, it still does not contain a ban on arms supplies to unauthorized non-state entities," Churkin told reporters. "This is a considerable systematic flaw that will unavoidably affect the effectiveness of the implementation of the Arms Trade Treaty.
He said Moscow would take a hard look at the treaty before deciding whether to sign it.
China, the world's third-largest arms supplier with $1.8 billion in sales, according to the Stockholm International Peace Research Institute, also abstained Tuesday.
The world's No. 1 arms supplier, the United States, voted in favor despite fierce opposition from the National Rifle Association, a powerful U.S. pro-gun lobbying group.
U.S. Secretary of State John Kerry said in a statement that the UN adopted the "strong, effective and implementable Arms Trade Treaty that can strengthen global security while protecting the sovereign right of states to conduct legitimate arms trade."
But it was unclear whether the U.S., whose arms sales totaled $8.8 billion last year, would be able to win congressional approval to join the treaty.
Several UN delegates said the treaty's effectiveness would be limited if major arms exporters refuse to sign it.
The Iranian, Syrian and North Korean delegations cast the sole votes against the treaty.
Iran, which is under a UN arms embargo over its nuclear program, is eager to ensure that its arms imports and exports are not curtailed, while Syria's government is embroiled in a two-year civil war and relies on arms from Russia and Iran, envoys said.
North Korea is also under a UN arms embargo due to its nuclear weapons and missile programs.
Echoing Churkin, Syrian UN Ambassador Bashar Ja'afari said his government opposed the Arms Trade Treaty because it does not ban the sale of weapons to non-state actors. He, however, was referring specifically to what his government describes as "terrorists" active in Syria.
The treaty does not ban transfers to armed groups but says all arms transfers should be subjected to rigorous risk and human rights assessments first.
The treaty will be open for signature on June 3 and will enter into force 90 days after the 50th signatory ratifies it. Mexican UN Ambassador Luis Alfonso de Alba told reporters that it normally takes two to three years for a treaty to come into force, but said he hoped it would happen sooner in this case.
Material from Reuters is included in this report.