TIMELINE: Iranian election and aftermath

(Reuters) - Here is a summary of the main developments in the aftermath of Iran's June 12 presidential election, which took place against a background of tension with the West over Tehran's nuclear program.

June 13 - Hardline incumbent Mahmoud Ahmadinejad officially wins presidential election with nearly 63 percent of the vote compared with 34 percent for reformist challenger Mirhossein Mousavi, authorities say. Thousands of protesters clash with police. Mousavi calls result a "dangerous charade".

June 14 - Mousavi says he has formally asked Iran's Guardian Council to annul the election.

June 15 - Seven people are killed during a huge march by Mousavi supporters in central Tehran, state media says. There are also pro-Mousavi demonstrations in the cities of Rasht, Orumiyeh, Zahedan and Tabriz.

June 16 - Leading Iranian reformist Mohammad Ali Abtahi, a former vice-president, is arrested, his office says.

-- The Guardian Council says it is ready to carry out a partial recount of ballots but rules out annulling the poll.

-- Tens of thousands of pro-Mousavi demonstrators march in northern Tehran. Ahmadinejad's supporters mobilize thousands of demonstrators in central Tehran.

-- Authorities ban foreign journalists from leaving their offices to cover street protests.

June 17 - Thousands march in central Tehran.

-- Ahmadinejad defends the legitimacy of the vote, telling a cabinet meeting it has "posed a great challenge to the West's democracy," Mehr news agency reports.

-- Saeed Laylaz, editor of business daily Sarmayeh, and pro-reform activist Mohammadreza Jalaiepour are arrested, a reformist source says.

June 18 - Thousands of Mousavi's backers rally in Tehran to mourn those killed in the mass protests.

-- A spokesman for the Guardian Council says it has begun examining 646 complaints submitted after the June 12 vote.

-- Iran's English-language state television has reported eight people killed in five days of protests. The ISNA news agency, quoting provincial officials, says 88 people were arrested in post-election unrest in the city of Mashhad and up to 60 people in Tabriz in the northwest.

June 19 -- Supreme Leader Ayatollah Ali Khamenei says protest leaders would be responsible for any bloodshed if rallies continued against the election, which he said Ahmadinejad had won fairly by 11 million votes.

June 20 -- The Guardian Council says it is ready to recount a tenth of the votes in the disputed election.

-- Riot police are deployed in force, firing teargas and using batons and water cannon to disperse groups of several hundred Iranians who had gathered across Tehran.

-- A suicide bomber blows himself up near the shrine of Iran's revolutionary founder Ayatollah Ruhollah Khomeini in Tehran, Iran's semi-official Mehr news agency reports.

-- State television says more than 450 people are detained during clashes in Tehran in which at least 10 people are killed.

June 21 -- Mousavi urges supporters to continue protests, issuing an oblique appeal to security forces to show restraint.

-- Ahmadinejad accuses the United States and Britain of interfering in Iran's affairs.

June 22 -- Hardline Revolutionary Guards issue a statement saying they will "firmly confront in a revolutionary way rioters and those who violate the law". Police break up a protest in Tehran hours after the Guards issued their statement.

-- People in Tehran again chant "Allahu Akbar" (God is greatest) from their rooftops at nightfall.

June 23 - Guardian Council again rules out annulment of the election saying there has been no major polling irregularities.