The assembly voted 154-3 for a resolution that will open the treaty for signature from June. Syria, North Korea and Iran – which had blocked the treaty last week – voted against it. Russia was among the 23 abstentions.
The first major arms accord since the 1996 Comprehensive Nuclear Test Ban Treaty would cover tanks, armored combat vehicles, large-caliber artillery systems, combat aircraft, attack helicopters, warships, missiles and missile launchers, as well as small arms and light arms.
It would aim to force countries to set up national controls on arms exports. States would also have to assess whether a weapon could be used for genocide, war crimes or by terrorists or organized crime before it is sold.
Every country is free to sign and ratify the treaty, which will take effect after the 50th ratification from among the 193 UN member states, which could take up to two years.
For more than a decade, activists and some governments have been pushing for international rules to regulating the arms trade.
Hopes of reaching agreement at a U.N. negotiating conference were dashed in July when the U.S. said it needed more time to consider the proposed accord – a move quickly backed by Russia and China. In December, the U.N. General Assembly decided to hold a final negotiating conference to agree on a treaty and set last Thursday as the deadline.
After two weeks of intensive negotiations, there was growing optimism as the deadline approached that all 193 member states would approve the final draft treaty by consensus - a requirement set by the United States. This time, the U.S. was prepared to support the final draft treaty. But Iran, North Korea and Syria objected.
Iran  said the treaty had many "loopholes," is "hugely susceptible to politicization and discrimination," and ignores the "legitimate demand" to prohibit the transfer of arms to those who commit aggression. Syria cited seven objections, including the treaty's failure to include an embargo on delivering weapons "to terrorist armed groups and to non-state actors." And North Korea said the treaty favors arms exporters who can restrict arms to importers that have a right to legitimate self-defense and the arms trade.
Both Iran and North Korea are under U.N. arms embargoes over their nuclear programs, while Syria is in the third year of a conflict that has escalated to civil war and is under U.S. and European Union sanctions. Amnesty International said all three countries "have abysmal human rights records - having even used arms against their own citizens."