A group of Iranian dissidents last week claimed their sources confirmed that Iran was working on its nuclear program at an undeclared location in Iran's northern Qazvin province.
Ali Shirzadian, a spokesman for the Atomic Energy Organization of Iran, told the official Islamic Republic News Agency that the allegations were baseless.
"Such rumors are intended to distort the true image of Iran's peaceful nuclear program and are circulated by Western countries," he said.
Iranian dissidents with the National Council of Resistance Iran claimed in 2002 to have evidence regarding Iran's nuclear work at Natanz, though analysts said Tehran was essentially flaunting its program at the time.
Iran is facing mounting international pressure to come clean on its nuclear program. The U.N. Security Council in June slapped Tehran with sanctions because of its controversial program.
Yukiya Amano, the director general of the International Atomic Energy Agency, told delegates during a meeting Monday in Vienna that it was unfortunate Iran has decided to thwart the work of nuclear inspectors.
"I learned with great regret about Iran's decision to object to the designation of two inspectors who recently conducted inspections in Iran," he said.