Timeline: Key events since the Islamic revolution

A chronology of key events since the return of Ayatollah Ruhollah Khomeini to Iran on February 1, 1979 after he had lived in exile for 14 years in Iraq and France for opposing the regime.

Khomeini led the 1979 Islamic Revolution and on February 11, 1979, he achieved victory as the army stepped aside.

April 1, 1979: The Islamic Republic of Iran is proclaimed following a referendum.

November 4: Militants take 52 Americans hostage inside the US embassy in Tehran. They demand the extradition of the Shah in the US at the time for medical treatment to face trial in Iran.

January 25, 1980: Abolhasan Bani Sadr is elected the first President of the Islamic Republic.

July 27: The exiled Shah dies of cancer in Egypt.

September 22: Iraq invades Iran after border skirmishes and a dispute over the Shatt Al Arab waterway. This marks the beginning of a war that lasted eight years.

January 20, 1981: The American hostages are freed after 444 days in captivity.

June 22: Bani Sadr is dismissed, who later flees to France.

July 3, 1988: 290 passengers and the crew of an Iran Air Airbus are mistakenly shot down by the USS Vincennes.

July 20: Iran accepts a ceasefire agreement with Iraq following negotiations in Geneva under the aegis of the UN.

June 3, 1989: Ayatollah Khomeini dies. On June 4, President Khamenei is appointed new supreme leader.

August 17: Ali Akbar Hashemi Rafsanjani is sworn in as the new president.

November 3: The US releases $567 million (about Dh2 billion) of frozen Iranian assets.

September 11, 1990: Iran and Iraq resume diplomatic relations.

1995: US imposes oil and trade sanctions over Iran's alleged sponsorship of "terrorism" seeking to acquire nuclear arms and hostility to the Middle East process. Iran denies the charges.

May 23, 1997: Mohammad Khatami wins the presidential election with 70% of the vote, beating the conservative ruling elite.

June 2001: President Khatami is re-elected after winning just under 77% of the vote. He starts his second term in August.

January 2002: US President George Bush describes Iraq, Iran and North Korea as an "axis of evil".

September: Russian technicians begin construction of Iran's first nuclear reactor at Bushehr despite strong objections from US.

September 2003: UN nuclear watchdog, IAEA, gives Tehran weeks to prove it is not pursuing an atomic weapons programme.

June 2004: Iran is rebuked by the IAEA for failing to fully cooperate with an inquiry into its nuclear activities.

November: Iran agrees to suspend most of its uranium enrichment under a deal with the European Union.

June 2005: Mahmoud Ahmadinejad, Tehran's ultra-conservative mayor, wins a run-off vote in presidential elections, defeating cleric and former president Akbar Hashemi Rafsanjani.

August-September: Tehran says it has resumed uranium conversion at its Isfahan plant and insists the programme is for peaceful purposes. IAEA finds Iran in violation of the nuclear Non-Proliferation Treaty.

January 2006: Iran breaks IAEA seals at its Natanz nuclear facility.

February: IAEA votes to report Iran to the UN Security Council over its nuclear activities. Iran resumes uranium enrichment at Natanz.

April: Iran says it has succeeded in enriching uranium at Natanz.

August 31: UN Security Council deadline for Iran to halt its work on nuclear fuel passes. IAEA says Tehran has failed to suspend the programme.

December: The UN Security Council votes to impose sanctions on Iran's trade in sensitive nuclear materials and technology. Iran condemns the resolution and vows to speed up uranium enrichment work.