A group of hardliners physically assaulted Iran's former president Mohammad Khatami during the annual Quds Day rally in Tehran on Friday, reformist website Parlemennews.ir reported.

"A group of hardliners assaulted Mohammad Khatami," the website reported.

"During the scuffle, his turban fell off and they wanted to beat him. But supporters resisted them and the riot police promptly intervened."

Khatami's brother Mohammad Reza Khatami said the former president, who is a key supporter of Iranian opposition groups, was "not hurt."

"Some people shouted slogans against him," the brother told AFP.

"He is home now. He is not hurt and he is fine."