The agency called on Pyongyang to adhere to past nuclear agreements and allow the U.N. inspectors expelled last month to return to work.
International Atomic Energy Agency chief Mohamed ElBaradei told reporters in Vienna that his agency would file a report with the Security Council -- a move that could trigger sanctions against North Korea -- should the Communist country's defiance continue.
"I hope [North Korea] will seize this opportunity," ElBaradei said. "Compliance and not defiance is the way towards a solution."
In its resolution, the IAEA said it "deplores in the strongest terms" North Korea's decision to remove U.N. inspectors and monitoring equipment and demanded Pyongyang allow the IAEA "to verify that all nuclear material ... is declared and is subject to safeguards."
Assistant Secretary of State John Wolf said the U.S. was pleased with the decision, saying the resolution "makes clear that unless the DPRK [North Korea] takes all necessary steps to implement the required measures, it will be in further non-compliance with the safeguards agreement."
Last month, North Korea moved to restart parts of its main nuclear weapons complex amid a dispute with the U.S. over a 1994 nuclear freeze agreement. In that deal, North Korea agreed to suspend its nuclear weapons program in exchange for shipments of fuel oil and U.S. help in building two light water reactors.
The U.S. ended the oil shipments after North Korea admitted it had been pursuing a program to produce weapons-grade uranium for several years. Pyongyang has said it now needs the nuclear facility to power the country's electrical systems.
The IAEA resolution comes as U.S. officials began two days of meetings with South Korean and Japanese diplomats in Washington. Officials from the three countries are expected to discuss a South Korean plan to mediate between the North and the U.S.
White House spokesman Ari Fleischer told reporters the U.S. will "work shoulder to shoulder" with South Korea on the nuclear issue, saying, "South Korea's offers are always appreciated and we work together."
Meanwhile, North Korea released a statement saying it would increase its "self-defensive military capability" to deal with the "U.S. intensified policy to invade and stifle it with nukes."
The official Korean Central News Agency said that the U.S. was fabricating claims Pyongyang represented a missile threat. The news agency said that "this goes to clearly prove that the U.S. intends to launch a military intervention" against North Korea.
"If the U.S. unleashes a nuclear war on the Koran peninsula, it will not escape its destruction," the news agency said.
Speaking to reporters last week, President Bush said he believed there would be a peaceful resolution to the Korea conflict, saying "it's a diplomatic issue, not a military issue, and we're working all fronts."