The brother of a British law graduate imprisoned in Tehran after trying to enter a men-only volleyball match has appealed to UK politicians to do more behind the scenes to secure his sister's release.
Iman Ghavami told VICE News that "nothing has changed" for his sister Ghoncheh, despite interventions by the UK prime minister and the delivery of a 375,000 signature petition to Iran's United Nations mission.
"I want the UK government to put as much pressure as possible on at the same time as maintaining a healthy relationship with the Iranian government," he said.
"I think maybe behind the scenes they can do more. More lobbying, negotiations."
Iman Ghavami's comments come at the same time as the UK is negotiating a delicate rekindling of diplomatic relations with Iran.
British Prime Minister David Cameron met the Iranian president, Hassan Rouhani, in New York on Wednesday for the first time since the 1979 Islamic Revolution — a landmark moment in strained relations between the two countries.
Cameron raised concerns about the imprisonment of Ghoncheh Ghavami in Iran during his meeting with Rouhani.
A statement from Downing Street said: "The Prime Minister ... raised the treatment of dual UK/Iranians nationals, in particular the case of Ms Ghoncheh Ghavami, underlining the impact that such cases had on Iran's image in the UK."
Iman Ghavami, 28, who lives in London, said he hoped that the warming of relations between the countries could expedite his sister's release.
He said: "I know the politicians are kind of limited when they're in public, but I'm sure behind the scenes they can do much more."
Ghoncheh Ghavami has been held in Tehran's notorious Evin Prison since June 30 and has spent nearly 50 days in solitary confinement.
The 25-year-old was arrested after trying to watch a volleyball match at the Azadi stadium on June 20, flouting the country's ban on women attending sporting events.
She was questioned for four hours and then released, but rearrested days later while attempting to collect her belongings from the police station, after officers discovered she was a dual British-Iranian citizen.
She was formally charged for the first time on Tuesday with "propaganda against the regime," which carries a possible prison sentence of several years.
Her parents have been able to visit her four times since her detention.
Imam Ghavami said: "Each day that goes by is a day of agony for them."
"They have no control over when she calls. For the first few weeks my mum was just there by the phone all day hoping they would call. And early on the pattern of the phone calls were kind of irregular."
Imam Ghavami attempted to hand-deliver two full boxes of signatures petitioning for his sister's release to Iran's United Nations mission in New York, but was turned away by security guards.
The petition on Change.org, which has since grown to more than 440,000 signatures, will be sent by email instead.
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