UN inspectors found "nothing to be worried about" in a first look at a previously secret uranium enrichment site in Iran last month, the International Atomic Energy chief said.

In interviews with CNN and The New York Times, Mohamed ElBaradei also said he was examining possible compromises to unblock a draft nuclear cooperation deal between Iran and three major powers that has foundered over Iranian objections.

The nuclear site, which Iran revealed in September three years after diplomats said Western spies first detected it, added to Western fears of covert Iranian efforts to develop atom bombs. Iran says it is enriching uranium only for electricity.
   
ElBaradei was quoted by The New York Times as saying his inspectors' initial findings at the fortified site beneath a desert mountain near the Shi'ite holy city of Qom were "nothing to be worried about."    

"The idea was to use it as a bunker under the mountain to protect things," ElBaradei, alluding to Tehran's references to the site as a fallback for its nuclear program in case its larger Natanz enrichment plant were bombed by a foe like Israel.

"It's a hole in a mountain," he said. The outgoing IAEA chief told CNN it was intended to be a "passive defense" of its nuclear technology in the event of an attack.

ElBaradei told CNN the agency's inspectors had received "quite good cooperation" when they visited Qom. The IAEA has declined to comment on whether the inspectors came across anything surprising or were able to obtain all the documentation and on-site access they had wanted at the remote spot about 160 km (100 miles) south of Tehran.

Details are expected to be included in the next IAEA report on Iran's disputed nuclear activity due in mid-November.

The inspectors' goal was to compare engineering designs to be provided by Iran with the actual look of the facility, interview scientists and other employees, and take soil samples to check for any traces of activity oriented to making bombs.
   
Western diplomats and analysts say the site's capacity appears too small to fuel a nuclear power station but enough to yield fissile material for one or two nuclear warheads a year. - Reuters