The offer to talk with the opposition was broadcast by state television, which quoted the Guardian Council’s spokesman, Abbas Ali Kadkhodaei, as saying: “The presidential candidates will be invited to the meeting to be held early next week to express their ideas and ask any questions in the presence of the Guardian Council’s members.”

The meeting would include Moussavi, Mehdi Karroubi and Mohsen Rezai.

Iran has been in tumult since early Saturday, when, just hours after the close of polls in Friday’s presidential election, Iranian authorities declared a landslide victory for the incumbent, Mahmoud Ahmadinejad.

In the unfolding battle of wills, the Government worked on many fronts to disrupt the outside world’s view of the unrest, banning coverage of the demonstrations, arresting journalists, threatening bloggers and trying to block websites like Facebook and Twitter, which have become vital outlets for information about the confrontation. None of this week’s mass gatherings have been given official authorisation and reporters have been formally barred from leaving their offices to cover them.

The senior prosecutor in the central province of Isfahan, where there have also been tense demonstrations, went so far as to say protesters could be executed under Islamic law.

Meanwhile, human rights groups accused the authorities of rounding up prominent figures, including former Foreign Minister Ibrahim Yazdi. International Campaign for Human Rights in Iran claimed he was arrested at a hospital in Tehran while undergoing treatment on Wednesday.

State television’s Press TV reported on its website that Moussavi was already set to address a rally on Saturday, called by a group of reformist clerics loyal to former President Mohammed Khatami who has thrown his support to the Opposition.