NEW DELHI, India (CNN) -- Iran broke international law by not disclosing sooner its recently revealed uranium enrichment site, the head of the United Nation's nuclear watchdog agency said.
IAEA's Mohamed El Baradei says he does not think Iran has an ongoing nuclear weapons program.
But the U.N. does not have credible evidence that Iran has an operational nuclear weapons program, Mohamed ElBaradei of the International Atomic Energy Agency said Tuesday.
"Iran has been on the wrong side of the law in so far as to inform the agency at an earlier date," ElBaradei told CNN's sister station in India, CNN-IBN. "Iran was supposed to inform us on the day it was decided to construct the facility. They have not done that."
Iran has previously denied breaking the law.
"According to the [IAEA's] current governing rules, there was no urgency in reporting anything about this installation and we could have not announced it, but we did so on order to contribute to trust-building and transparency and we did so much sooner than the required time," Ali Akbar Salehi, director of the Iranian Atomic Energy Agency, said Sunday.
ElBaradei's comments came ahead of an expected meeting Thursday between Iran's nuclear negotiator, Saeed Jalili, and representatives of the five permanent U.N. Security Council members, plus Germany.
The meeting is scheduled to take place in Geneva, Switzerland.
Last week, Iran wrote a letter to the IAEA revealing the existence of the facility. The admission prompted U.S. President Obama and the leaders of Britain and France to chide the Islamic republic publicly and threaten further sanctions.
Iran claims its nuclear enrichment program is intended for peaceful purposes, but the international community accuses the country of continuing to try to develop nuclear weapons capability.
The facility is located on a military base near the city of Qom, about 100 miles (160 kilometers) southwest of Tehran, and is thought to be capable of housing 3,000 centrifuges, according to the officials and the IAEA.
That is not enough to produce nuclear fuel to power a reactor, but sufficient to manufacture bomb-making material, according to a U.S. diplomatic source who read the letter.
Iran has said there is no nuclear material at the site. It announced Tuesday it will allow the IAEA to inspect the facility but did not offer a timetable.
"But we need to go and impress on him that we need to go, our inspector needs to go and inspect the facility and establish the facts, to discuss with them," ElBaradei said.