Eid celebrations in Iran could finally herald Nazanin Zaghari-Ratcliffe’s release from prison – with husband Richard hoping for news of clemency within the “next ten to twenty days”.

Nazanin could theoretically be awarded clemency on Wednesday, that’s when Nazanin’s lawyer has been told to return to the Iranian prosecutors’ office, but Richard Ratcliffe told the Ham&High it was more realistic to hope for movement in her case “perhaps the week after”.

Nazanin has now been in prison for more than four years, and her furlough from jail was extended “until a decision on clemency is made” on Wednesday May 20.

Richard told this newspaper: “My instinct is it’s more likely he [her lawyer] gets told to come back next week. And maybe the week after that. It is a big decision. Normally in Iran that means it is a slow one.”

After Nazanin’s furlough was extended until the clemency decision, the prime minister’s official spokesperson said: “Nazanin should not be in prison at all and that she should be allowed to return to the UK to be with her family.

“The PM and foreign secretary have raised it on a number of occasions. The Iranians are very clear as to our position.”

Richard said this capped a week that had been “more positive than we were expecting”.

Frustrated by Iranian stalling, Nazanin’s family had pushed unsuccessfully for the UK ambassador to Iran to visit her under house arrest.

Richard said: “We were starting to get jumpy, which is why we were pushing so hard for the ambassador to visit. Clearly they thought it would be disruptive.”

He added that the decision to leave Nazanin out of jail – and the treatment of other foreign hostages by the Iranian regime – could bode well, saying: “There’s no point putting her back into prison if they are going to give us clemency. There were other cases both public and not in public domain where people have been sentenced just recently. You could read that as bad news, or as a consolidation of assets by the regime.

“I would expect after Eid we will be looking towards an decision. Ten days time, that’s where I would expect something to be decided if it were to be a good decision. If we go beyond 20 days I would expect that would mean there’s something blocking it.”