Updated

A confidential analysis by members of the U.N. nuclear watchdog concludes Iran has “sufficient information to be able to design and produce a workable” nuclear bomb, the New York Times reported.

The International Atomic Energy Agency report, titled "Possible Military Dimensions of Iran’s Nuclear Program," states Tehran has done extensive research and testing to perfect nuclear arms such as firing test explosives and designing warheads and paints a picture of a complex program.

The Associated Press described fragments of the report last month, but more details appeared Friday on the Web site of the Institute for Science and International Security, run by nuclear expert David Albright.

Senior European officials described the conclusions of the report to the Times but said its contents had been revised and were "not ready for publication as an official document."

IAEA head ElBaradei reportedly opposes adopting a "confrontational strategy" with Iran and a dispute between senior IAEA members and ElBaradei has recently erupted over whether or not to release the report. ElBaradei has called into question its completeness and reliability, the Times reported.

Additional details of the report emerged as ElBaradei arrived in Tehran to arrange an inspection of the uranium enrichment facility near the holy city of Qom.

President Obama and the leaders of France and Britain have accused Iran of keeping its construction hidden from the world for years. Obama said last month that Iran's actions "raised grave doubts" about its promise to use nuclear technology for peaceful purposes only.

ElBaradei has also said Tehran was "on the wrong side of the law" over the new plant and should have revealed its plans as soon as it decided to build the facility.

Iran President Mahmoud Ahmadinejad hit back Saturday at accusations the country had sought to hide its construction of the new nuclear site, arguing that Tehran reported the facility to the U.N. even earlier than required.

"The U.S. president made a big and historic mistake," Iranian state TV quoted Ahmadinejad as saying. "Later it became clear that (his) information was wrong and that we had no secrecy."

Click here to read more on this story at the New York Times.