BRUSSELS, June 19 (RIA Novosti) - European Union leaders on Friday urged Iran not to clamp down on peaceful demonstrations against the country's presidential election results.

Iran has been swept by mass demonstrations over alleged ballot fraud in the landslide reelection of the hardline president on June 12, and the EU announcement said all Iranians should be able to gather and express their opinions on the vote.

The document, issued on the last day of the two-day summer summit of leaders of the EU's 27 member-states in Brussels, called on the Iranian authorities not to use force against peaceful demonstrators.

Iranian Supreme Leader Ayatollah Ali Khamenei on Friday rejected the possibility that vote rigging affected the result of the country's presidential election and said that people's opinions should be expressed in elections, not on the street.

In his sermon for Friday prayers, he dismissed the possibility of electoral fraud by the state, and said Ahmadinejad's margin of victory, at more than 11 million votes, was too great for the election to have been stolen.

Official results gave the incumbent 63% of the vote, with reformist challenger Mir Hossein Mousavi getting 34%.

Calling on the country to unite after days of protests against the results of the presidential elections, he said that allegations of fraud should be dealt with through legal channels.

He stressed that everyone involved, both candidates and voters, supported the state and the revolution, but said his views were closer to the policies of Ahmadinejad than his opponent.