UNITED NATIONS – The U.N. Security Council on Wednesday approved new sanctions against Iran over its suspect nuclear program that target Iran’s powerful Revolutionary Guard, ballistic missiles and nuclear-related investments.

The resolution imposing a fourth round of sanctions against Iran was approved by a vote of 12-2 with Lebanon abstaining and Brazil and Turkey voting “no.”

U.S. President Barack Obama said the resolution puts in place “the toughest sanctions ever faced by the Iranian government, and it sends an unmistakable message about the international community’s commitment to stopping the spread of nuclear weapons.”

But he stressed that the door to diplomacy and negotiations remains open, and told White House reporters that he would “like nothing more than to reach the day” when Iran answers all questions raised by the International Atomic Energy Agency so sanctions can be lifted.

Iran’s President Mahmoud Ahmadinejad dismissed the resolution, telling a meeting in Dushanbe, Tajikistan, “we don’t recognize sanctions,” and that “for us they are annoying flies, like a used tissue.”

At U.N. headquarters, Iran’s U.N. Ambassador Mohammad Khazaee defended the country’s right to produce nuclear energy, reiterated that Iran opposes nuclear weapons on religious and ethical grounds, and accused the United States, Britain and their allies of abusing the Security Council to attack Iran.

“No amount of pressure and mischief will be able to break our nation’s determination to pursue and defend its legal and inalienable rights,” Khazaee said.

U.S. Ambassador Susan Rice dismissed Khazaee’s statement as “ridiculous” and “reprehensible” and declared that “these sanctions are as tough as they are smart and precise.”

The Security Council imposed limited sanctions in December 2006 and has been ratcheting them up in hopes of pressuring Iran to suspend enrichment and start negotiations on its nuclear program.

The first two resolutions were adopted unanimously and the third by a vote of 14-0 with Indonesia abstaining.