Days before Nazanin Zaghari-Ratcliffe is set to go on hunger strike over her treatment in Iranian prison, Amnesty UK have slammed a “sinister and disturbing” release of documentary footage.

Earlier this week Iranian state TV aired a programme which has been slammed as a “smear”.

This comes in response to the letter written by Nazanin and her fellow detainee Narges Mohammadi in which they announced a hunger strike in protest at restrictions on their access to medical treatment.

Kate Allen, Amnesty International UK’s Director, said: “Coming soon after Nazanin and her fellow prisoner of conscience Narges Mohammadi announced their intention to go on hunger strike in protest at being denied medical treatment, the appearance of this footage is sinister and disturbing.

“The Iranian authorities have a track record of airing propaganda videos and making statements about individuals as part of a calculated attempt to publicly smear them.”

The Centre for Human Rights in Iran have also condemned the footage’s release.

A spokesperson said: “This sensationalist film masquerading as a documentary was broadcast on state TV after Nazanin and prominent political prisoner Narges Mohammadi announced in an open letter that they would be going on hunger strike. “Nazanin’s accusers hope the film will be covered by media outlets instead of the ongoing violations of her and other political prisoners’ rights by Iran’s security forces and hardline judicial officials.”

Nazanin’s hunger strike is set to begin on Monday and last until Wednesday. At the time of writing the Iranian authorities have not accepted any of the pair’s demands.

Richard Ratcliffe has previously told this newspaper that Nazanin is again worried after having found lumps in her breast, and also concerned about neurological symptoms which are causing her neck and back pain.

MPs including Hampstead and Kilburn’s Tulip Siddiq and shadow Foreign Secretary Emily Thornberry spoke out to condemn Iran’s treatment of Nazanin in parliament on Monday.

Ms Thornberry said Iran was “digging its diplomatic grave”.

Foreign Secretary Jeremy Hunt has also repeatedly tweeted in support of Nazanin’s plight.