President Mahmoud Ahmadinejad's main challenger is calling on authorities to cancel Friday's presidential election, saying it is the only way to restore public trust, AP reported. Mir Hossein Mousavi, who has accused authorities of election fraud, urged his supporters to continue their «civil and lawful» opposition to results showing Ahmadinejad won by a landslide. He advised police to stop violence against protesters. Mousavi's statement was posted Sunday on one of his campaign Web sites. It is his first since two days of violent clashes between Ahmadinejad opponents and police erupted on the streets of Tehran. Mousavi has claimed he was the true winner of the election. -- SPA