THE FIVE-YEAR-long detainment of a British mother in Iran is a “blot on British diplomacy”, her husband has said.

British-Iranian dual national Nazanin Zaghari-Ratcliffe has been detained in Tehran since 2016, when she was sentenced to five years in prison over allegations, which she denies, of plotting to overthrow the Iranian government.

Her sentence is scheduled to end this weekend and her husband Richard has said he has spent the last five years “swinging between hope and despair” as his wife remained in Iran.

“It is shocking that what started off as a mum and a baby on holiday could be allowed to last for five years,” he told the PA news agency.

“There’s no ambiguity in that, that’s just staggering.

It is a blot on British diplomacy and clearly Iranian hostage-taking is outrageous.

Mrs Zaghari-Ratcliffe, 42, has been out of prison since last spring due to the coronavirus crisis, and has been under house arrest at her parents’ home in Tehran.

She was arrested at Tehran’s Imam Khomeini airport while travelling to show her young daughter, Gabriella, to her parents in April 2016.

Gabriella is now of school age and is “counting down” the days until her mother comes home.

Mr Ratcliffe explained: “She’s got a calendar that she crosses off each day.

“She’s in that sense counting down and I think probably still at this point treating it like an advent calendar, so the days will come off and then the magic delivery will happen.

“In terms of her wider understanding, for a long time she’s been asking ‘when’s mummy coming back, when’s mummy coming back’.

“Hopefully this won’t be tough for her psychologically if mummy doesn’t come back at the end of all those days on the calendar.

“She’s had a lot of experience of grown-ups promising her that mummy’s coming home and then mummy not coming home.”

Mrs Zaghari-Ratcliffe’s original sentence is due to end on 7 March, but she appeared in court last November on charges of spreading propaganda against the regime.

Speaking at the time, Mr Ratcliffe called the charges “spurious”, saying the case presented the same evidence used when she was convicted in 2016.

He told PA he wants to know what the government’s plan is for getting his wife back to the UK.

Mr Ratcliffe said: “If she comes home on the day, I don’t need to know what you’re doing, thank you very much, and I’m sorry for all of the rude things I’ve said in the media, and I’ll come out and say thank you very much and be very gracious.

“But if she doesn’t come home, I want to know what you’re going to do on 8 March.

“There’s no ambiguity, that’s proper straightforward hostage-taking,” he added.

“Do I have confidence that the government is going to get her home on 7 March?

“No, I’m standing here worried.”

A spokesman for the Foreign, Commonwealth and Development Office said: “The Foreign Secretary and FCDO remain in close contact with Zaghari-Ratcliffe and her family, and continue to provide our support.

“We do not accept Iran detaining dual British nationals as diplomatic leverage. The regime must end its arbitrary detention of all dual British nationals.

“We continue to do everything we can to secure the release of arbitrarily detained dual British nationals so that they can be reunited with their loved ones.”