Exiled opposition National Council of Resistance of Iran reports uranium enrichment facility at Natanz and heavy water plant at Arak.
The existence of sites at Natanz and Arak is confirmed by satellite photographs. The U.S. accuses Tehran of "across-the-board pursuit of weapons of mass destruction". Iran agrees to inspections by the International Atomic Energy Authority (IAEA).
Iranian President Mohammed Khatami reveals that Iran has unearthed uranium deposits and announces plans to develop a nuclear fuel cycle. IAEA chief Mohammed ElBaradei travels to Iran with a team of inspectors to begin probing Tehran’s nuclear plans.
International Atomic Energy Agency (IAEA) report says Iran failed to comply with nuclear Non-Proliferation Treaty by keeping its atomic program secret for 18 years.
Traces of highly enriched weapons-grade uranium found at Natanz.
More enriched uranium discovered, prompting urgent calls for Iran to sign a voluntary protocol formalizing a tougher inspection regime.
After meeting French, German and British foreign ministers, Tehran agrees to stop producing enriched uranium and formally decides to sign the Additional Protocol. No evidence is produced to confirm the end of enrichment.
Iran signs protocol allowing snap inspections of nuclear facilities.
Abdul Qadeer Khan, the father of Pakistan’s nuclear bomb, is reported to have sold Iran nuclear weapons technology.
IAEA report says Iran experimented with polonium-210, which can be used to trigger the chain reaction in a nuclear bomb. Iran did not explain the experiments. Iran again agrees to suspend enrichment, but again does not.
Tehran is criticized by the IAEA for trying to import magnets for centrifuges and for not offering "full, timely and pro-active" co-operation with inspectors.
IAEA orders Iran to stop preparations for a large-scale uranium enrichment. U.S. Secretary of State Colin Powell labels Iran a growing danger and calls for the U.N. Security Council to impose sanctions. Iran says it has resumed large-scale conversion of uranium ore into gas.
February 2005: President Mohammad Khatami says no Iranian government will give up nuclear technology program.
Iran announces plans to resume uranium conversion at Isfahan.
European Union states warn that any resumption of conversion would end negotiations linked to trade and economic issues. Iran agrees to wait for detailed proposals from the Europeans at the end of July.
May 20, 2005:
Iran has been using front companies to skirt international export controls and purchase a graphite compound that can be used in nuclear and conventional arms, an Iranian exile said.
July 28, 2005:
Iranian Resistance revealed, Iran has been using front companies to import a type of steel that can be used for the casing of a nuclear bomb and for machines that can enrich uranium to weapons-grade, an exile group said on Thursday
Hardliner Mahmoud Ahmadinejad is installed as Iranian president, as Tehran pledges an "irreversible" resumption of enrichment. Iran resumes sensitive fuel cycle work at its uranium conversion facility near Isfahan.
August 18, 2005:
Iran has manufactured thousands of centrifuges capable of enriching uranium to weapons grade in a covert nuclear program, an Iranian dissident group said Thursday.
August 9, 2005:
Iran has manufactured about 4,000 centrifuges capable of enriching uranium to weapons grade, Iranian Resistance said. Alireza Jafarzadeh told The Associated Press the centrifuges Ã¢â¬â which he said are unknown to the U.N. nuclear watchdog agency Ã¢â¬â are ready to be installed at Iran’s nuclear facility in Natanz.
September 1, 2005:
According to reliable reports from inside Iran obtained by the Iranian resistance recently, the clerical regime is trying vigorously to obtain Beryllium metal to be used in its secret nuclear project, which is under the supervision of the Revolutionary Guards and the Ministry of Defense. It has smuggled sizeable amounts of Beryllium to Iran surreptitiously to be used for its secret nuclear project.
September 2, 2005:
IAEA report confirms Iran has resumed uranium conversion at Isfahan.
November 21, 2005:
Tehran is building nuclear-warhead capable missiles with help from North Korean experts in a vast underground complex, Iranian opposition sources said.
December 25, 2005:
Iranian regime rejected an offer from Russia to conduct uranium enrichment activities on its soil for Iran.
January 10, 2006:
Iran removes U.N. seals at Natanz enrichment plant and resumes nuclear fuel research.
February 4, 2006:
IAEA votes to report Iran to U.N. Security Council. Iran ends U.N. snap inspections the next day. Iran restarts small-scale uranium enrichment 10 days later.
March 8, 2006:
IAEA report to Security Council says it cannot verify Iran’s atomic activities are peaceful.
April 11, 2006:
Iran says it has produced low-grade enriched uranium suitable for use in power stations; IAEA confirms this.
April 12, 2006:
Iran can deliver on its threat Tuesday to enrich uranium, said the Iranian opposition, who said the Islamic republic has the know-how and tools to make nuclear bombs within two or three years.
April 17, 2006:
New satellite imagery indicate Iran has expanded its uranium conversion site at Isfahan and reinforced its Natanz underground uranium enrichment plant against possible military strikes, a U.S. think tank said.
April 28, 2006:
IAEA report to the Security Council confirms Iran has flouted council demands to suspend enrichment.
June 12, 2006:
Fresh evidence has emerged that Iran is working on a secret military project to develop nuclear weapons that has not been declared to United Nations inspectors responsible for monitoring Iran’s nuclear program. Nuclear experts working for the International Atomic Energy Agency in Vienna are pressing the Iranians to make a full disclosure about a network of research laboratories at a secret military base outside the capital Teheran code-named Zirzamin 27.
July 31, 2006:
Security Council demands Iran suspend nuclear activities by August 31.Council makes first legally-binding demands in resolution and threatens sanctions.
August 26, 2006:
Iranian President Mahmoud Ahmadinejad is to open a heavy water plant Saturday that will feed a nuclear research reactor currently under construction.
August 31, 2006:
IAEA announces Iran has not met deadline to suspend program and has resumed enriching uranium.
September 14, 2006:
Iran restarted a laser uranium enrichment program under the cover of a medical and industrial laboratory equipment company, according to the Iranian opposition.
September 26, 2006:
Russia and Iran agree start-up date of September 2007 for Iran’s first nuclear power station at Bushehr.
November 14, 2006:
IAEA report says Iran has started experimental chain of 164 linked centrifuges, feeding uranium gas into them for enrichment.
December 23, 2006:
Security Council votes for sanctions and gives 60 days to suspend enrichment. Iran calls the resolution illegal.
January 22, 2007:
Iran bars entry to 38 IAEA inspectors after hardliners demand retaliation for sanctions.
February 20, 2007:
Chief negotiator Ali Larijani says Iran will give guarantees there will be no deviation towards nuclear weapons.
February 21, 2007:
A 60-day grace period to stop enrichment expires.
February 22, 2007:
IAEA says Iran has installed two cascades of 164 centrifuges in Natanz with another two almost completed. These cascades represent efforts to expand research-level enrichment of nuclear fuel into "industrial scale" production.
February 23, 2007:
Iran has changed the names of companies involved in its nuclear program and has created a new set of front companies to avoid sanctions imposed by the United Nations, according to the Iranian opposition.
March 14, 2007:
U.S., British, French, German, Russian and Chinese diplomats at the United Nations reach a tentative deal on imposing fresh sanctions. President Mahmoud Ahmadinejad dismisses any new sanctions resolution the next day as "a torn piece of paper."
March 24, 2007:
The Security Council unanimously approves new arms and financial sanctions against Iran for refusing to suspend uranium enrichment.
April 9, 2007:
Iran says it has begun the "industrial stage" of nuclear fuel production with mass production of (uranium enrichment) centrifuges and the launch of industrial-scale enrichment.