A prominent human rights lawyer in Iran, Nasrin Sotoudeh, is facing accusations of espionage on top of charges already leveled against her, Sotoudeh's lawyer says.

"First it was only accusations of spreading antiestablishment propaganda, but now it is espionage," Sotoudeh's lawyer Payam Derafshan told the government's official IRNA news agency.

Derfashan said authorities have not provided any evidence to back the charge.

"There is no evidence in her file for the charge of spying, no report by the Intelligence Ministry to explain how she is a spy," Derafshan told the AFP news agency.

Sotoudeh, who earlier in 2018 represented several women detained for publicly protesting the compulsory hijab, was arrested in June.

She says she was told that she will serve a five-year prison sentence after being convicted in absentia.

Sotoudeh -- the co-winner of the European Parliament's 2012 Sakharov Prize for Freedom of Thought -- has denied all charges against her.

As outspoken critic of the Iranian establishment, Sotoudeh previously has spent several years in prison on security charges, including acting against Iran's national security.

She has defended journalists, rights activists, and juveniles.

Based on reporting by AFP and IRNA