Jailed Iranian-British activist Nazanin Zaghari-Ratcliffe faces extra 15 years behind bars

A British-Iranian woman jailed for five years in Iran during a visit with her toddler daughter could face an extra 15 years behind bars.

Nazanin Zaghari-Ratcliffe appeared in court at Iran's notorious Evin prison on Sunday, where she was told the Revolutionary Guards paramilitary force had brought new charges against her.

She is currently serving five years in jail for allegations of plotting a "soft toppling" of the regime.

Although Zaghari-Ratcliffe was promised the prospect of early release next month, the new allegations could see 15 years added to her sentence.

The new charges relate to her previous work with the BBC and Thomson Reuters Foundation, her husband Richard Ratcliffe said.

Both media outlets have a troubled history with the Iranian regime.

"Thanks to the Revolutionary Guards' antics, this is a justice system that can no longer look its victims in the eye, can no longer look itself in the mirror," he said in a statement.

Republican Guards attempted to have Zaghari-Ratcliffe confess to accusations she "recruited spies" in 2016, something she refused to do.

Thomson Reuters Foundation have described the charges against her as "ludicrous" and that the impact is being felt on her young family.

"This inhumane treatment is breaking up a young family and has already caused irreparable damage to Nazanin’s physical and mental health," said Monique Villa, the CEO of the Thomson Reuters Foundation.

Ultra-conservatives in the Iranian government - including the Republican Guards and judiciary - are looking to regain influence in the country following the country's nuclear agreement.

The 2015 deal with world powers was seen as a victory for moderates in the country, including President Hassan Rouhani, with the economy boosted by the prospect of sanctions relief.

The clampdown by conservatives has seen the arrest of dual-nationals, foreigners, moderate politicians and even members of the negotiating team.