The report "contains erroneous, misleading and unsubstantiated information," said the letter, dated Sept. 12, sent to Peter Hoekstra, the Republican chairman of a Congressional committee and the Bush administration, which was leaked to Washington Post.

The International Atomic Energy Agency (IAEA) said errors in the report suggested Iran's nuclear fuel program was much more advanced than a series of IAEA reports and Washington's own intelligence assessments had determined. However, the fact is Iran is far from that capability, the IAEA said.

The IAEA's letter noted five significant errors in the report, including the alleged claiming that Iran is producing weapons-grade uranium. It was the first time the IAEA has publicly rebutted U.S. allegations about its Iran investigation.

The situation is compared with the Iraq war in 2003. The letter "recalled clashes between the IAEA and the Bush administration before the 2003 Iraq war over intelligence regarding weapons of mass destruction, and underlined growing tensions over Iran's current nuclear capacities," reported The Scotsman.

"This is like prewar Iraq all over again," said David Albright, a former nuclear inspector who is president of the Washington-based Institute for Science and International Security. "You have an Iranian nuclear threat that is spun up, using bad information that's cherrypicked, and a report that trashes the inspectors."

The report's author, Fredrick Fleitz, is a onetime CIA officer who had been a special assistant to John Bolton, the Administration's former point man on Iran at the State Department. Bolton, now U.S. ambassador to the United Nations, had been highly influential during President Bush's first term in crafting a policy that rejected talks with Tehran.