WASHINGTON (Reuters) - Here is a timeline on Iran’s nuclear program since the last talks in Geneva in 2009 between Tehran and the six powers seeking to ensure Tehran does not develop an atomic bomb - Britain, China, France, Germany, Russia and the United States.
October 1 - Iran meets six world powers in Geneva and approves in principle a plan to send 75 percent of its low-enriched uranium to Russia and France, where it would be made into special fuel for a Tehran reactor making medical materials.
October 25 - U.N. nuclear experts inspect a newly disclosed enrichment plant being built near the Shi’ite holy city of Qom.
October 30 - Iran tells the International Atomic Energy Agency (IAEA) it wants fresh nuclear fuel for a reactor in Tehran before it will agree to ship some enriched uranium stocks to Russia and France, according to U.N. officials.
November 18 - Tehran says will not send enriched uranium abroad but will consider swapping it for nuclear fuel within Iran.
November 19 - U.S. President Obama warns Iran of the consequences of its failure to respond to the nuclear deal.
November 27 - The IAEA’s 35-nation governing board censures Iran for developing the plant near Qom in secret and demands Iran freeze the project. Iran rejects the demand.
November 29 - Iran says it plans to build 10 more enrichment sites.
January 19 - Iran rejects key parts of the deal to send abroad for processing most of its enrichment material.
February 2 - President Mahmoud Ahmadinejad says Iran is ready to send enriched uranium abroad, apparently easing his position.
February 9 - Iran begins making higher-grade nuclear fuel, enriched to a higher level of 20 percent, at Natanz facility.
February 18 - An IAEA report suggests, bluntly and for the first time, that Iran is actively pursuing nuclear weapons capability.
April 19 - Iran says it will start work on a new uranium enrichment plant, in addition to the Natanz and Qom sites.
May 12 - Ahmadinejad says U.N. resolutions aimed at increasing sanctions against Iran over its nuclear program “are not worth a penny” and Tehran will give no ground to pressure
May 17 - Iran, Brazil and Turkey sign a nuclear fuel swap deal. Iran says it has agreed to transfer 1.2 tonnes (2,646 lbs) of its low-enriched uranium to Turkey within a month in return for higher-enriched nuclear fuel for a medical research reactor.
May 31 - An IAEA report shows Iran’s low-enriched uranium stockpile is up to 2.4 tonnes (5,300 lbs). So, even if the proposed 1.2 tonnes were shipped out it would still leave Iran enough material for a nuclear weapon if enriched to higher levels. June 9 - The U.N. Security Council votes to expand sanctions against Iran to hit its banking and other industries.
June 24 - The U.S. Congress approves tough new unilateral sanctions aimed at squeezing Iran’s energy and banking sectors, which could also hurt foreign companies doing business with Tehran. They are signed into law on July 1.
July 26 - The EU imposes tighter sanctions on Iran, aiming to block oil and gas investment and curtail its refining.
— Iran says it is ready to hold talks on a nuclear fuel swap without conditions.
July 30 - Iran says it will never give up its right to refine uranium, but could suspend higher-level enrichment if a fuel swap can be agreed with foreign powers.
August 30 - Iran announces it will produce in a year the nuclear fuel needed for the medical isotope reactor in Tehran.
September 6 - An IAEA report says Iran has told inspectors that it had accumulated around 2.8 tonnes of low-enriched uranium, about 816 lbs (370 kg) more than in May.
September 29 - The Bushehr nuclear power plant will begin supplying energy in early 2011, a senior official says, signaling a delay of several months after the Stuxnet computer virus is believed to have affected operations there.
October 26 - Iran says it has begun loading fuel into Bushehr.
November 23 - A new IAEA report says Iran told the agency on November 22 that 28 cascades — which normally have 164 centrifuges each — are now enriching uranium.
— Iran tells inspectors it has produced around 7,017 lbs (3,183 kg) of LEU since February 2007, about 840 lbs (380 kg) (more than at the beginning of August. That total is enough for at least two atomic bombs, if enriched to 90 percent purity, experts say.
November 29 - Nuclear scientist Majid Shahriyari is killed in a bomb attack on his car in Tehran, an attack which Iran has blamed on Western intelligence services.
December 5 - Iran’s nuclear energy chief Ali Akbar Salehi says Iran will use domestically produced uranium concentrates, known as yellowcake, for the first time at a key nuclear facility, cutting reliance on imports of the ingredient for nuclear fuel.
December 6 - Talks begin in Geneva between Iranian nuclear negotiator Saeed Jalili and EU foreign policy chief Catherine Ashton, who is leading the talks for the six powers.
December 7 - Iran and major powers agreed to meet in Istanbul in late January. (Meeting is set for January 20)
Writing by David Cutler, London Editorial Reference Unit, Editing by Jackie Frank