THE GWENT-based sister-in-law of a woman locked up in Iran on spying charges has spoken of her deteriorating mental state ahead of the third anniversary of her imprisonment tomorrow.

Cwmbran GP Rebecca Radcliffe also told South Wales Argus the family of Nazanin Zaghari-Radcliffe will mark the three year anniversary of her imprisonment tomorrow by visiting a park near her London home.

Mrs Zaghari Ratcliffe was imprisoned on April 3, 2016 after she was accused of spying by the Iranian government.

The charity worker was detained with her young daughter Gabriella at an airport in Tehran as they planned to return to Britain.

South Wales Argus: Nazanin Zaghari-Ratcliffe with her daughter Gabriella

Nazanin Zaghari-Radcliffe with her daughter Gabriella

Every year on April 3, Ms Radcliffe joins the rest of the family at the London park to support each other through the “difficult time”.

In the park, said Ms Radcliffe, is a tree where they plan to leave messages of hope and support for Mrs Zaghari-Radcliffe – who is struggling to keep her spirits up in captivity.

“Nazanin is really low at the moment,” said Ms Radcliffe.

South Wales Argus:

(Mrs Zaghari-Radcliffe has been in an Iranian prison for three years)

“Home is becoming a distant concept for her. We want to remind her of what she can look forward to when she gets home.

“It’s always a difficult time of year for us.”

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The family are planning to write notes reminding Mrs Zaghari Radcliffe of the good things waiting for her at home, and are asking members of the public to add their own notes.

“We want people to help her remember the good things by adding notes to a special tree in the park.

"People can send them into us, and we’ll add them to the tree.

“We call it our ‘one day tree’.

“We want to keep the dream alive for Nazanin that one day soon we will all be together again.”

If you want to add a note, you can put it at the bottom of Mrs Zaghari-Radcliffe's Change.org petition, where the family will read it.

On May 13, local supporters of the campaign to free Mrs Zaghari-Radcliffe are invited to join the family at Pettigrew Tea Rooms in Cardiff to help make a knitted chain, symbolising Nazanin’s continued imprisonment.

Each knitted link will be made up of over 1000 stitches – to mark the number of days of her imprisonment.

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“For those readers that wish to knit some chains but unable to come to the event they can post the chains to me at Cwmbran Village Surgery,” added Ms Radcliffe.

“Knitting instructions as follows: 70 stitches x 17 rows, plain/garter stitch 4mm knitting needles, any colour.

“Thanks to the Argus and your readers for continuing to keep our story alive.”

Mrs Zaghari-Ratcliffe, 40, is serving a five-year sentence in Tehran's notorious Evin Prison after she was convicted of membership of an illegal group.

The trial by a Revolutionary Court in Tehran was widely condemned as unfair and she strenuously denies the charges against her.

South Wales Argus:

(Her husband, Richard, delivered flowers to the Iranian embassy in London on Mother's Day)

On Mother's Day, Mrs Zaghari-Radcliffe's husband, Richard, delivered flowers to the Iranian Embassy in London.

Speaking on Sunday, a Foreign Office spokesman said: "It is deeply disappointing that Mrs Zaghari-Ratcliffe will be spending yet another Mother's Day without her daughter Gabriella.

"We constantly review which further steps are available to secure Nazanin's release, and will continue to be guided by what we consider is in the best interests of Mrs Zaghari-Ratcliffe, and of all dual national consular cases in Iran."