Dozens of Iranian students burnt pictures of President Ahmadinejad and chanted “Death to the dictator” as he gave a speech at a university in Tehran yesterday.

Never has the hardline leader faced such open hostility at a public event, which came as Iran opened a conference questioning whether Nazi Germany murdered six million Jews.

One student activist said that the protest was against the “shameful” Holocaust conference and the “fact that many activists have not been allowed to attend university”. The conference “has brought to our country Nazis and racists from around the world”, he added.

Mr Ahmadinejad responded by saying: “Everyone should know that Ahmadinejad is prepared to be burnt in the path of true freedom, independence and justice”, according to an Iranian students’ news agency. He accused the protesters of being “Americanised”.