Iranian students on Monday staged a rare demonstration against President Mahmoud Ahmadinejad, lighting a firecracker and burning the head of state's photograph as he spoke at Amir Kabir Technical University in Tehran, the official Islamic Republic News Agency reported.

According to the agency the students called Ahmadinejad a dictator, and the president allowed their chants.

"We have resisted dictatorship for many years - from before the 1979 Islamic Revolution - and nobody can bring back a dictatorship even in the name of freedom," the agency quoted the president as telling the students at the university.