The measure is expected to go to the full UN General Assembly for a vote in late November or early December.
A UN General Assembly committee on Thursday voted to launch negotiations on a new treaty outlawing nuclear weapons despite fierce opposition from the world's nuclear powers.
A resolution presented by Austria, Ireland, Mexico, Nigeria, South Africa and Brazil was adopted by a vote of 123 to 38, with 16 abstentions, following weeks of lobbying by the nuclear powers for 'no' votes.
The non-binding resolution provides for negotiations to begin in March next year on the new treaty, citing deep concern over the "catastrophic humanitarian consequences of any use of nuclear weapons."
Four of the five UN Security Council nuclear powers — Britain, France, Russia and the United States — voted against the resolution while China abstained, as did India and Pakistan.
Israel, Australia and Turkey also voted against the resolution. North Korea and most Arab Gulf countries voted in favour of the resolution.
Japan, which has long campaigned against the use of nuclear weapons, voted against it, as did South Korea, which is facing a nuclear threat from North Korea.
Opponents argued that nuclear disarmament should be addressed within negotiations on the Nuclear Non-Proliferation Treaty (NPT).
Beatrice Fihn, executive director of the International Campaign to Abolish Nuclear Weapons, described the vote as a "historic moment" in the decades-long drive for a nuclear-free world.
"This treaty won't eliminate nuclear weapons overnight. But it will establish a powerful, new international legal standard, stigmatising nuclear weapons and compelling nations to take urgent action on disarmament."
The measure is expected to go to the full General Assembly for a vote in late November or early December.