It's time for the United States to hold Iran accountable.

A British-Iranian grandfather will be entering his seventh year in prison for alleged espionage charges in Iran, his family said.

Kamal Foroughi, a 77-year-old oil and gas company consultant, was detained in 2011 before being convicted of espionage and possessing alcohol two years later.

Friday marks six years since the detention of Mr Foroughi, who strenuously maintains his innocence.

The family of the dual national have long campaigned for his release from Evin prison in Tehran - the same jail where another dual national, Nazanin Zaghari-Ratcliffe, is being held.

Earlier this year, to mark six years since Mr Foroughi last saw his family, his son Kamran delivered a letter to Foreign Secretary Boris Johnson calling for his release. It was signed by 219 MPs and a number of peers.

The Foreign Office has said it has raised the pair's individual cases with the Iranian government "and will continue to do so at every opportunity".

Kamran Foroughi said the 72 months and 2,193 days his father has been in jail felt "like a lifetime".

He said his father had been taken to hospital five times for tests in the recent months, adding "We, his family, are very worried he will die in prison".

Mr Foroughi has had no visitors in over 2,000 days, he said.

A Change.org petition calling for his release, directed at leaders in Britain, Iran and the EU, been signed by more than 200,000 supporters.

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