Iran's top electoral body today rejected calls to scrap the country's disputed election, ending hopes of a rerun demanded by angry opposition supporters.

The announcement by the Guardian Council on Iran's state-run English language Press TV was another sign the regime is determined to crush unrest, the worst since the 1979 Islamic Revolution, rather than seek compromise.

Government warnings to the protesters have intensified in recent days, with Iran's supreme leader ordering them off the streets and the feared Revolutionary Guards threatening a tough crackdown. At least 17 people have been killed in near-daily demonstrations.

In a boost for the embattled regime, Russia said that it respects the declared election result, which the Iranian government described as a landslide victory for hard-line President Mahmoud Ahmadinejad.

The US and many European countries have refrained from challenging the election outcome directly, but have issued increasingly stern warnings against continuing violence meted out to demonstrators.

Ahmadinejad's main challenger, Mir Hossein Mousavi, has said the election was a fraud and insists he is the true winner.

The Guardian Council found "no major fraud or breach in the election," a spokesman said. "Therefore, there is no possibility of an annulment taking place."

Yesterday the Guardian Council admitted there had been voting irregularities in 50 districts, including local vote counts that exceeded the number of eligible voters. However, the council said the discrepancies were not widespread enough to affect the result.

After a huge opposition rally a week ago, protests have become smaller, but demonstrators have been more willing to confront Iranian troops.

Yesterday Tehran riot police fired tear gas and live bullets to break up about 200 protesters paying tribute to those killed in the protests, including Neda Agha Soltan, whose shooting was captured on video and circulated worldwide.

Helicopters hovered overhead as riot police fired live rounds and lobbed tear gas to break up the gathering. Security forces ordered people to keep walking and prevented even small groups from gathering.

Ms Soltan's boyfriend Caspian Makan, a 37-year-old photojournalist in Tehran, said she had not been deterred by the risk of protesting. "She only ever said that she wanted one thing, she wanted democracy and freedom for the people of Iran," he said.