The UN Security Council has voted unanimously to impose sanctions on Iran's trade in sensitive nuclear materials and technology, an effort to stop enrichment work that could be used in bombs.
"Today we are placing Iran in the small category of states under Security Council sanctions," acting US Ambassador Alejandro Wolff told the council before the 15-0 vote, which followed two months of tough negotiations.
Iran, which refused to end its uranium enrichment work in exchange for economic incentives earlier this year, immediately condemned the resolution as illegal and said it would not affect its "peaceful" nuclear activities.
The resolution demands Iran end all research on uranium enrichment, which can produce fuel for nuclear power plants as well as for bombs, and halt all research and development on methods of producing or delivering atomic weapons.
The thrust of the sanctions is a ban on imports and exports of dangerous materials and technology relating to uranium enrichment, reprocessing and heavy-water reactors, as well as ballistic missile delivery systems. The measure is less restrictive than the original draft, drawn up by Britain, France and Germany, due to Russian objections.
A ban on Iran's oil exports was not considered.
In Tehran, Foreign Ministry spokesman Mohammad Ali Hosseini told state-run television the resolution "cannot affect or limit Iran's peaceful nuclear activities but will discredit the decisions of the Security Council."
He said Iran would continue to install 3,000 centrifuge units at Natanz, the site of a uranium enrichment plant.
Tehran's UN Ambassador, Javard Zarif, accused the Security Council and the United States of a double standard by punishing Iran while ignoring Israel's nuclear arsenal. "Iran has simply thumbed its nose at the council and defied international law," Britain's UN Ambassador Emyr Jones Parry told the council, adding that he remained committed to resolve the dispute through negotiations.
While Britain, France and Germany, sponsors of the resolution, urged Iran to return to negotiations, the United States sought tougher measures, such as an end to credits for Iran and a halt to arms sales. It urged the Europeans, Russia and China to do the same.
The resolution is under Chapter 7, Article 41 of the UN Charter, which makes enforcement mandatory but restricts action to non-military measures, and Russia's UN Ambassador Vitaly Churkin emphasized this point. Russian President Vladimir Putin, whose government had hesitated over supporting the resolution and succeeded in watering down parts of it, called US President George W Bush yesterday after reviewing the measure until the last minute.
Russia, which is building an $800 million light-water reactor for Tehran that is exempted in the resolution, has tried to maintain close ties with Iran but is also concerned about any bomb-building intentions Iran may have.
The resolution includes a freeze on financial assets abroad of 12 individuals and 10 organizations from Iran associated with nuclear programmes to prevent them from buying dangerous materials.
But there are numerous qualifications, including exempting contracts made prior to the adoption of the resolution.