The husband of Nazanin Zaghari-Ratcliffe has told Boris Johnson to stop “getting distracted” from the fight to release her from an Iranian jail, more than three years on from her initial detention.

Ms Zaghari-Ratcliffe, a dual British-Iranian citizen, has been imprisoned in Tehran since 2016, when she was arrested and accused of spying during a trip to see her family in Iran.

Mr Johnson was widely criticised for his handling of her case when he was the foreign secretary in 2017 after he mistakenly said Ms Zaghari-Ratcliffe had been “teaching people journalism” in the country. He was later forced to apologise.

Richard Ratcliffe, her husband, has accused the UK of “enabling the abuse of British citizens” and said Mr Johnson’s government “needs to take a much more robust stand against Iranian hostage-taking”.

Ms Zaghari-Ratcliffe is due to go on hunger strike in solidarity with a British-Australian academic who has been sentenced to 10 years in prison on spying charges, according to Mr Ratcliffe.

Kylie Moore-Gilbert, the academic, started an open-ended hunger strike before Christmas and has called on Scott Morrison, Australia’s prime minister, to do more to secure her release.

Nazanin Zaghari-Ratcliffe – in pictures Show all 20 1 /20 Nazanin Zaghari-Ratcliffe – in pictures Nazanin Zaghari-Ratcliffe – in pictures 2018 Nazanin Zaghari-Ratcliffe hugs her daughter Gabriella, in Iran after she was allowed to leave the Iranian prison, she is being held in, for three days. Zaghari-Ratcliffe was arrested during a holiday with her toddler daughter in April 2016. Iranian authorities accuse her of plotting against the government. Her family denies this, saying says she was in Iran to visit family. Free Nazanin Campaign/AP Nazanin Zaghari-Ratcliffe – in pictures Nazanin Zaghari-Ratcliffe with her husband Richard Ratcliffe and their daughter Gabriella. Nazanin is serving a five-year prison sentence for allegedly plotting to overthrow Iran's government. PA Nazanin Zaghari-Ratcliffe – in pictures June 2016 Richard Ratcliffe's daughter Gabriella had her British passport confiscated and was stranded in Iran with her grandparents after her mother Nazanin was jailed. He left left a giant birthday card on the doorstep of the Iranian embassy in central London to mark her second birthday in June 2016. PA Nazanin Zaghari-Ratcliffe – in pictures Nazanin has spent some of her prison sentence in solitary confinement. PA Nazanin Zaghari-Ratcliffe – in pictures Nazanin Zaghari-Ratcliffe with her husband Richard and daughter Gabriella. Family Handout Nazanin Zaghari-Ratcliffe – in pictures July 2016 Richard Ratcliffe delivering a letter of petition with his mother Barbara Ratcliffe and MP Tulip Siddiq, to 10, Downing Street on the 100th day of her detention, on July 12, 2016. Getty Nazanin Zaghari-Ratcliffe – in pictures Supporters of Nazanin Zaghari-Ratcliffe held a vigil outside the Foreign and Commonwealth Office to mark her 707 days in captivity. Getty Nazanin Zaghari-Ratcliffe – in pictures January 2017 Richard Ratcliffe holds a '#Free Nazanin' sign and candle during a vigil for for wife on January 16, 2017. The vigil, being held outside the Iranian Embassy in London marks one year since the Washington Post journalist Jason Rezaian and other US-Iranian dual-nationals were released from prison in Iran. Getty Nazanin Zaghari-Ratcliffe – in pictures Nazanin with her daughter Gabriella before they were detained by Iranian authorities. Change.org Nazanin Zaghari-Ratcliffe – in pictures September 2017 Gabriella, who is three-years-old in this picture, has now spent two years away from her mother. Richard Ratcliffe Nazanin Zaghari-Ratcliffe – in pictures November 2017 Foreign Secretary Boris Johnson meets with Richard Ratcliffe over Nazanin's case. They meet just days after Johnson told a parliamentary committee that she was in Iran "training journalists". WPA Pool/Getty Nazanin Zaghari-Ratcliffe – in pictures November 2017 Actor Emma Thompson braved pneumonia to support Richard Ratcliffe in leading demonstrators before a march in support of Nazanin in November. Reuters Nazanin Zaghari-Ratcliffe – in pictures November 2017 Richard Ratcliffe after the march said: 'It is profoundly moving to see so many people here.' REUTERS Nazanin Zaghari-Ratcliffe – in pictures November 2017 A picture of Nazanin Zaghari-Ratcliffe shown on Iranian state TV as part of a report that made fresh allegations against her. They said she had been recruiting for banned broadcast services, as well as 'opposition cyber teams'. Nazanin Zaghari-Ratcliffe – in pictures December 2017 Iranian president Hassan Rouhani greets British Foreign Secretary Boris Johnson at the presidential office in Tehran, Iran. Johnson visited Tehran to discuss the fate of detained Nazanin Zaghari-Ratcliffe. EPA Nazanin Zaghari-Ratcliffe – in pictures Nazanin Zaghari-Ratcliffe with her daughter Gabriella. PA Nazanin Zaghari-Ratcliffe – in pictures December 2017 Photos of Richard Ratcliffe and his wife Nazanin Zaghari-Ratcliffe on display at their home in north London. Mr Ratcliffe said he believed there was "still a chance" she may be released from an Iranian prison in time for a dream Christmas together. Unfortunately that didn't happen. PA Nazanin Zaghari-Ratcliffe – in pictures February 2018 Richard Ratcliffe delivers a petition and a letter addressed to the Iranian Deputy Foreign Minister Abbas Araghchi to demand her release, at the Iranian Embassy in London on February 21, 2018. He also left support letters for his spouse in the country's embassy, amid a visit by a deputy foreign minister. AFP/Getty Nazanin Zaghari-Ratcliffe – in pictures August 2018 Foreign Secretary, Jeremy Hunt meeting Richard Ratcliffe. Hunt has pledged to do everything possible to secure the release of a charity worker jailed in Iran Jeremy Hunt/PA Nazanin Zaghari-Ratcliffe – in pictures August 2018 Nazanin Zaghari-Ratcliffe hugs her daughter Gabriella, in Iran after she was allowed to leave the Iranian prison, she is being held in, for three days. Zaghari-Ratcliffe was arrested during a holiday with her toddler daughter in April 2016. Iranian authorities accuse her of plotting against the government. Her family denies this, saying says she was in Iran to visit family. PA

“If President Trump can get Americans home with all the baggage there, then there is no earthly reason why the UK cannot,” Mr Ratcliffe said, referring to successful negotiations in recent years to secure the release of US hostages.

“It is a question of priorities, and the prime minister not getting distracted again.”

He added that Ms Zaghari-Ratcliffe, who also refused food on Christmas Eve, told him on Monday: “I really can't keep going on like this, someone needs to do something.”

“When people are desperate, a hunger strike is the only weapon people have,” Mr Ratcliffe said.

“It is to get the Iranian regime to notice, but it is also to cut through the complacency of their own governments, to remind them of their promises to get things done or leave no stone unturned.”

In 2017, Mr Johnson's comment about Ms Zaghari-Ratcliffe teaching journalism was cited as evidence against her when she appeared in an Iranian court.

A spokesperson for the Foreign Office said the department remains “extremely concerned about the welfare of Ms Zaghari-Ratcliffe and other British-Iranian dual nationals detained in Iran.”

“We continue to raise her case at the highest levels, are in regular contact with her family and press Iran for her release,” they added.

Mr Ratcliffe also expressed his support for Ms Moore-Gilbert and called on the Australian and British governments to “step up” their efforts to secure her release.

“Five days on dry hunger strike is becoming critical, and our thoughts go out to Kylie and her family for all this ordeal,” he told The Guardian on Sunday.