Updated

The U.N. nuclear watchdog needs more power and more cooperation to deal with Iran and North Korea, the head of the agency said Friday.

"I work on the basis of legal authority and information. If I don't have the authority, if I don't have the information, I am paralyzed," said Mohamed ElBaradei (search), director-general of the International Atomic Energy Agency.

Iran and North Korea "have been giving the international community the run-around" when it comes to its nuclear programs and possible weapons ambitions, ElBaradei said in an interview with the British Broadcasting Corp.'s "HARDtalk (search)" program.

"That's why I have been kicking and screaming to say, `Give me more authority,"' he said. "If you really need me to do a good job, I need additional authority."

The Vienna-based nuclear agency has been pressuring Iran to sign an additional protocol to the Nuclear Nonproliferation Treaty (search), which would open the country to more intrusive and unannounced inspections. ElBaradei said the Iranians assured him a couple of days ago that they would sign, giving him more authority to act.

"I hope they will do it as early as possible," he said. "If you have nothing to hide, there no reason not to be transparent."

ElBaradei said he also was concerned about Iran following reports that the country has embarked on a uranium enrichment program.

The U.N. nuclear chief conceded that his agency should have known about the development of new nuclear facilities at Iran's Natanz nuclear facility, where IAEA experts found traces of highly enriched uranium.

The Iranians "have been acting in some way in a transparent manner" by opening several facilities to the agency in recent months, ElBaradei said. "But I need more transparency, a more proactive approach," he added.

ElBaradei said he had not given in to pressure when compiling a report on Iran ahead of the agency's Sept. 8 board meeting.

"Washington made it clear what they expect to see in the report. But that's their expectation," he said. "I work for 135 countries. I tell them: 'I give you all the facts. I will ... give you my assessment as we see it as an impartial organization."'

On North Korea, ElBaradei accused the secretive country of risky posturing by claiming to U.S. officials that it may test an atomic bomb.

"It is pretty dangerous," he said in the BBC, which was taped Thursday. "The fact that they are using it to intimidate, to blackmail. I think it sends a very bad signal."

Nonetheless, ElBaradei said diplomats must be patient in trying to convince North Korea to halt any nuclear weapons program. "It will take time, but I think the only way to resolve it is through dialogue," he said. "We would like to work with them."

North Korea expelled inspectors from the U.N. nuclear watchdog agency in December, shortly after it dismantled U.N. seals and monitoring cameras installed at the country's nuclear facilities. The facilities had been mothballed under the 1994 agreement.

Asked about Iraq, ElBaradei said the nuclear agency needs to complete its work to determine with any certainty that the Iraqis did not revive their atomic weapons program.

"There could be one," ElBaradei said. "I would be surprised if there were."

The Bush administration is running the post-war search in Iraq for weapons of mass destruction, but has yet to discover any.