The unrest in Iran is just "the beginning of a big movement" that could be more widespread than the demonstrations of 2009, the Nobel Peace Prize-winning Iranian lawyer Shirin Ebadi said in an interview Sunday.

"I think the protests are not going to end soon. It seems to me that we are witnessing the beginning of a big protest movement that can go well beyond the Green wave of 2009. It would not surprise me if it becomes something bigger," said Ebadi to the Italian newspaper La Repubblica.

A third night of unrest in Iran saw mass demonstrations across the country in which two people were killed, dozens arrested and public buildings attacked.The demonstrations are the biggest since the Green Movement protests of 2009 against the re-election of the ultra-conservative ex-president Mahmoud Ahmadinejad, which were violently repressed.

But now the roots of anger are above all economic and social, according to Abadi, who now lives in exile in London.

"In Iran, and it is not new, there is a very serious economic crisis. The corruption in the whole country is at appalling levels. The end of certain sanctions related to the nuclear agreement with Europe and the United States in 2015 did not bring real benefits to the population, contrary to what many expected," the lawyer said.

"Added to this is the fact that Iran has very high military expenditures. People are not willing to see so much money spent on it," she added.

"Young people are the most disappointed," Ebadi said, referring to the high unemployment, corruption and "the climate of censorship".

"The economic situation and the frightening gap between the rich and the poor, between those who enjoy well-being and those who cannot, are at the root of the protest," the 2003 Nobel Peace Prize-winner said.