The United Nations' International Atomic Energy Agency has struggled for years to verify that Iran's nuclear program is for purely peaceful purposes, as Iran insists, while other nations, particularly the United States, are equally adamant that Iran is trying to develop nuclear weapons in secret.

In November 2004, Iran entered an agreement with Britain, Germany and France to suspend its uranium enrichment activities. Enriched uranium is one of the cornerstones of a nuclear weapons program.

At that time, Iran reaffirmed its commitment to the nuclear Non-Proliferation Treaty saying it would not seek to acquire nuclear weapons. And the European nations guaranteed that Iran has the right to pursue a civilian nuclear program.

The debate over Iran's nuclear program failed to fade, however, and the Persian country's assertion that it has a right to nuclear energy helped propel the hard-line Islamic mayor of Tehran Mahmoud Ahmadinejad into the presidency in June 2005.

In March 2006, after talks between Iran and the European countries fell apart, the IAEA voted to refer the matter to the U.N. Security Council. A day later, Iran's top nuclear negotiator Ali Larijani said the country would resume uranium enrichment, and a defiant Ahmadinejad told Iran's semi-official news agency Mehr, "They (Western countries) are very angry with us, but it's not important to us because they cannot do anything and we are not scared of anything. If they could do something against us, they would not have wasted time to prepare the stage."

The U.N. Security Council met to discuss Iran's nuclear development but came to no conclusion, with Tehran contending the whole time that it had a right to pursue a nuclear program for civilian purposes.

Dealings with the IAEA
The Islamic Republic of Iran became a member of the IAEA in 1958, a year after the agency was established.

Iran began its nuclear power program in the mid-1960s under bilateral agreements with the United States and now has five research reactors and two partially constructed power reactors at Bushehr.

Due to concerns -- voiced primarily by the U.S. government -- that Iran may be working on developing nuclear weapons, IAEA inspectors visited Iran numerous times to retrieve information on the nuclear facilities and conduct environmental tests around the sites that Iran says are for civilian purposes only.

Concerns were elevated in mid-2002, when American intelligence learned of the existence of two secret nuclear facilities, a uranium enrichment facility at Natanz and a heavy water production plant near Arak.

		Space Imaging The sprawling Natanz nuclear facility in Iran

Traces of highly enriched uranium, which can be used for nuclear weapons, were found at the facility in Natanz in the summer of 2003. The substance was not on Iran's inventory of declared nuclear material. Iranian officials said the residue was from equipment purchased from other countries and would be next to impossible to trace.

After the discovery, the IAEA gave Iran until Oct. 31, 2003 to reveal all information about its nuclear programs to inspectors. A week before the deadline, Iran provided key documents, saying they fully disclosed the extent of the country's peaceful activities in the nuclear field.

But a report the IAEA released in November 2003 said Iran had been secretly experimenting on materials that could be made into nuclear weapons though there was no evidence a bomb was the ultimate goal.

"Iran has now acknowledged that it has been developing, for 18 years, a uranium centrifuge program, and, for 12 years, a laser enrichment program," the assessment found. "In that context Iran has admitted that it produced small amounts of LEU (low-enriched uranium), using both centrifuge and laser enrichment processes ... and a small amount of plutonium."

Plutonium production is generally associated with building nuclear weapons. Iran made the plutonium between 1988 and 1992 at the Tehran Nuclear Research Center to "gain experience in reprocessing chemistry," Iran said, according to the IAEA report, and later dismantled the equipment.

Iran has said the violations of the nuclear Nonproliferation Treaty that the U.N. agency outlined in its report were trivial, and that it had to hide certain nuclear activities because of sanctions that have been in place for decades.

The nuclear watchdog also has urged Iran to sign an additional protocol to the nuclear Nonproliferation Treaty that would allow more complete, snap inspections even at sites that are not declared under the NPT. Iran has said it is willing to sign the addendum but requires assurances that Western sanctions will be lifted and Tehran will receive nuclear technology for its energy needs. Little movement on either side has brought negotiations essentially to a standstill.

-- Compiled by Larisa Epatko for the Online NewsHour