Iran insisted it would go ahead with the uranium enrichment at the centre of the dispute. President Mahmoud Ahmadinejad said the U.N. resolution was "valueless" and should be thrown "in the waste bin like a used handkerchief."
But Russia and China, which have strong economic ties with Tehran and have at times resisted sanctions, fully backed the new U.N. move to blacklist dozens of Iranian military, industrial and shipping firms.
U.S. President Barack Obama said the sanctions, which also provide for inspections of suspect cargoes to and from Iran and tighten an arms embargo, would be vigorously enforced.
The resolution followed five months of arduous negotiations between the United States, Britain, France, Germany, China and Russia. With 12 votes in favour, it received the least support in the 15-nation council of the four Iran sanctions resolutions adopted since 2006.
Brazil and Turkey, angry at the West's dismissal of an atomic fuel deal with Iran that they said made new sanctions unnecessary, voted against. Lebanon, where the Iranian-backed militant group Hezbollah is in the government, abstained.
Brazilian President Luiz Inacio Lula da Silva called the resolution a mistake and his foreign minister said he doubted the sanctions would have any impact. But U.S. Secretary of State Hillary Clinton said in Colombia they would "slow down and certainly interfere with" Iran's nuclear ambitions.
The sanctions vote was delayed for more than an hour as the Brazilian, Turkish and Lebanese delegations awaited instructions from their capitals. Western diplomats said that Lebanon's abstention came after the Lebanese cabinet split 14-14 over whether to oppose the resolution or abstain.
The four Western powers had wanted tougher measures -- some targeting Iran's energy sector -- but Beijing and Moscow succeeded in diluting the steps outlined in the resolution.
"This council has risen to its responsibilities. Now Iran should choose a wiser course," U.S. Ambassador Susan Rice told the council after the vote.
Iran denies Western allegations that it is seeking atomic weapons, insisting that it only wants peaceful nuclear energy.
Tehran's envoy to the U.N. nuclear watchdog in Vienna said the sanctions would not alter Iran's nuclear program. "Nothing will change. The Islamic Republic of Iran will continue uranium enrichment activities," Ambassador Ali Asghar Soltanieh said.
China, which had hesitated for months before joining talks on new sanctions in January, called for full implementation of the new measures and urged Tehran to comply with international demands about its enrichment program.
In Washington, Obama said the new sanctions were the most comprehensive that Iran had faced and sent an unmistakable message. "We will ensure that these sanctions are vigorously enforced, just as we continue to refine and enforce our own sanctions on Iran," he said.
Israel, which has hinted it could bomb Iran's nuclear facilities the way it did Iraq's in 1981, said the new sanctions were an important step, but called for even broader economic and diplomatic measures.
Russia's Foreign Ministry may have had Israel in mind when it announced that the measures in the resolution "exclude the possibility of employing force.
The resolution calls for measures against new Iranian banks abroad if a connection to the nuclear or missile programs is suspected, as well as vigilance over transactions with any Iranian bank, including the central bank.
It also blacklists three firms controlled by Islamic Republic of Iran Shipping Lines and 15 belonging to the Islamic Revolutionary Guard Corps, as well as calling for setting up a cargo inspection regime like one in place for North Korea.
The resolution lists 40 companies in all to be added to a U.N. blacklist of firms whose assets worldwide are to be frozen for aiding Iran's nuclear or missile programs.
The only new blacklisted individual is Javad Rahiqi, head of an Iranian nuclear centre where uranium is processed. His assets will be blocked and he will face a foreign travel ban.
SEPARATE EU, U.S. SANCTIONS
EU diplomats said major European states plan to use the U.N. move to impose their own unilateral sanctions on Iran and could agree on them very soon.
U.S. Defence Secretary Robert Gates hinted that unilateral measures that the United States and its EU allies might approve could target Iran's oil and gas exports.
On Capitol Hill, House of Representatives Foreign Affairs Committee Chairman Howard Berman predicted the U.S. Congress would pass additional sanctions on Iran this month, without saying what they might be.
Richard Lugar, a Republican and one of the Senate's most respected voices on foreign policy, said he thought lawmakers should wait and see what the Europeans did before deciding on further U.S. sanctions.
Turkey and Brazil last month revived parts of a plan brokered by U.N. nuclear inspectors in October for Tehran to part with 1,200 kg (2,600 pounds) of low enriched uranium, or LEU, in return for fuel rods for a medical research reactor.
Iran's LEU proposal raised concerns, Russia, France and the United States said in a note to the U.N. watchdog International Atomic Energy Agency, according to diplomats in Vienna.
Iran had proposed to part with no more LEU -- potential atomic bomb material if enriched to a very high purity level -- than it did under the original October deal, even though its LEU stockpile had almost doubled since then, they said. Iran had also begun refining uranium to a higher level in February.
The first two U.N. Iran sanctions resolutions, adopted in 2006 and 2007, passed unanimously. The council approved a third set in 2008 with 14 "Yes" votes and one abstention.
The three rounds of punitive measures aimed at Iran's nuclear and missile industries have hurt its economy but failed to persuade its leadership to halt its nuclear program or come to the negotiating table. Analysts said the new sanctions were unlikely to persuade Tehran to stop enriching uranium.
I am very glad that on the day the UN hit Iran with sanctions the Iranian Ambassador Manouchehr Mottaki received the following treatment during a trip to Dublin. I filmed this footage of Iranian patriot Reza as he interrupts the ambassador and gets attacked by his security forces.
This from RTE news
I have more footage of yesterday's dramatic events in Dublin including similar but better images of the ambassador fleeing the scene as he gets pelted with eggs. It is a bit longer than the other videos I took so I am having difficulties downloading it. Bare with me.