THE SNP’s Westminster leader has called on Boris Johnson to do “everything we can politically and diplomatically” to ensure Nazanin Zaghari-Ratcliffe is returned safely as she faces a fresh court appearance.

Ian Blackford has demanded the Prime Minister makes sure all avenues have been explored in the “critical hours” following Zaghari-Ratcliffe's fresh court date today – and has accused the UK Government of having “failed Nazanin and her family”.

Zaghari-Ratcliffe, who is a dual UK-Iranian citizen has been held in Iran for the past five years amid accusations she plotted to overthrow the government – claims she has consistently denied. She has finished her sentence under house arrest due to the pandemic.

READ MORE: Continued detention by Iran of Nazanin Zaghari-Ratcliffe is 'outrageous,' insists husband Richard

It has been widely claimed that Zaghari-Ratcliffe and other British-Iranian dual nationals who have been jailed in Iran are being held hostage until the UK repays the debt arising from arms sales in the mid-1970s.

A report has warned that the 42-year-old is a victim of torture and requires urgent psychiatric treatment.

Mr Blackford has now written to the Prime Minster, insisting everything needs to be done to protect Zaghari-Ratcliffe from further action.

In his letter, Mr Blackford has demanded the UK Government does “everything it can in these critical hours to ensure the safe return of Nazanin Zaghari-Ratcliffe to the United Kingdom”.

He added: “Despite the positive news Nazanin's ankle tag had been removed, it was deeply concerning to hear she faces a fresh court date on Sunday. The following 48 hours will be vital in securing her release so she can return safely from Iran to the United Kingdom and be reunited with her family.

The Herald: SNP Westminster leader Ian BlackfordSNP Westminster leader Ian Blackford

“The UK Government has so-far failed Nazanin and her family. She has now been separated from her husband and young daughter for five years and her situation has been exacerbated by your own failures as Foreign Secretary.

“I urge you, as Prime Minister, to do all that you can politically and diplomatically to ensure the secure and full release of Nazanin Zaghari-Ratcliffe from the Iranian authorities so she can be reunited with her family and receive any medical support that she needs.”

Ms Zaghari-Ratcliffe's husband has said his family faces further uncertainty ahead of her return to court in Iran.

Richard Ratcliffe said his wife “remains in harm’s way” despite being released from house arrest last week after her five-year prison term expired.

The Herald: Richard RatcliffeRichard Ratcliffe

Mr Ratcliffe said that, while Foreign, Commonwealth and Development Office (FCDO) officials are “relieved” that Mrs Zaghari-Ratcliffe’s ankle monitor has been removed, they remain “cautious” about what could happen next.

“I don’t think they know what to expect on Sunday, and I don’t think we know what to expect on Sunday,” he said.

Downing Street said Boris Johnson had again demanded the release of Zaghari-Ratcliffe in a call with Iranian President Hassan Rouhani on Wednesday.

A No 10 spokesman said the Prime Minister had said “that while the removal of Nazanin Zaghari-Ratcliffe’s ankle monitor was welcome, her continued confinement remains completely unacceptable, and she must be allowed to return to her family in the UK”.

Amnesty International UK has called on Britain’s ambassador in Tehran to visit Zaghari-Ratcliffe before her court hearing today to show “maximum solidarity” with her.

Downing Street has previously said officials have been denied access to legal proceedings because Iran does not recognise dual nationality.