The supreme leader of Iran is addressing the nation for the first time since the disputed presidential election result led to mass protests and violence.

Followers of Mr Mousavi held a day of mourning in Tehran

Ayatollah Ali Khamenei is leading weekly Muslim prayers in the capital Tehran following six days of opposition rallies against the outcome of the vote.

Supporters of hardline President Mahmoud Ahmadinejad gathered to hear Khamenei speak, in a move intended to be a show of their strength.

Tens of thousands of followers of the defeated presidential candidate Mirhossein Mousavi held a sombre march on Thursday, wearing black and carrying candles in remembrance of those killed during clashes earlier in the week.

Some carried banners urging protesters to stay at home today but to gather again on Saturday.

Khamenei has urged Iranians to unite behind President Ahmadinejad but said he would consider a partial recount after allegations of vote-rigging.

The Guardian Council, which oversees elections in Iran, is investigating 646 complaints related to the presidential poll.

Objections include a shortage of ballot papers, pressure on voters to support a particular candidate and the barring of candidates’ representatives from polling stations.

Mr Mousavi and two other losing candidates have been invited to set out their grievances on Saturday with a decision about any possible recounts due on Sunday.

Iranian state media has reported eight people killed in protests since the election results were published on June 13.

A crackdown has been launched on international media, with foreign journalists banned from attending all rallies or other events without express authority.

Meanwhile, Iran’s intelligence ministry said it had uncovered a foreign-linked terrorist plot to plant bombs in mosques and other crowded places in Tehran during the election.

State media quoted a ministry statement as saying several terrorist groups had been discovered, adding they were linked to Iran’s foreign enemies, including Israel.