Nazanin Zaghari-Ratcliffe is revelling in her first taste of freedom in five years after the Iranian authorities removed her ankle tag at the weekend.

Hopes were raised that the 42-year-old British-Iranian’s ordeal was reaching the “endgame” after she was released from house arrest and had the tag removed.

Though she is due back in court on Sunday to face further charges, Nazanin is “not thinking about that at all”.

On Monday, her husband Richard Ratcliffe told HuffPost UK: “The difference in her life is seismic. I hadn’t appreciated just what a difference not having an ankle tag makes. For a year she’s not been able to go anywhere and for four years before that she’s been stuck in prison.

“Now, she can. Go and visit granny, her sister, her friends. It’s a different world. We all have a sense of what lockdown lifting is like but this is of a different order and that’s what she and her mum and her dad were so euphoric about yesterday, utterly really jubilant, like almost it was a bridal party – that kind of unadulterated happiness.

“And there I was, sitting guarded, not quite sure what to say and not quite sure what it meant. Whereas for her there was no ambiguity about it, what it meant was that it was a really good day.”

Nazanin, who normally lives in north London, was detained in 2016 as Iranian authorities made widely refuted spying allegations. She finished the latter part of her sentence under house arrest due to the Covid-19 pandemic.

Following her release on Sunday, she has been summoned back to court to answer new charges of spreading propaganda against the regime, which were brought against her in November.

On Monday, Richard and the couple’s six-year-old daughter Gabriella staged a vigil outside the Iranian embassy in Knightsbridge, central London. Richard attempted to deliver an Amnesty International petition of more than 160,000 signatures calling for his wife’s immediate release, but was turned away by someone speaking over the building’s intercom.

A small group of protesters stood in front of the embassy holding placards carrying the messages “free Nazanin” and “still not forgotten”.

Richard said: “We’re still in a game of chess. It’s still not within our control – there are still risks. But the lived experience of it is markedly better now than it was last week.”

And he added: “A week’s a long time in Iran in terms of politics. It’s very volatile. We could be in a relaxed environment which suddenly feels very spiky again.

“On Saturday she was taken to see the physiotherapist. Every trip at that point was being accompanied by prison guards, she was chaperoned everywhere. She got it into her head on Saturday that they weren’t going to take her to hospital, they were going to take her to prison and she got jittery and worried about what was going to happen. That was just in her head but it was a very real terror. It’s quite possible that those nightmares start to come back. It’s that structural jeopardy where you could get good news, you could get bad news and you’re left paralysed with uncertainty as to what awaits.”

If convicted of the charge, Nazanin could face another year in prison. And if the Iranian courts make the argument she is a repeat offender, they could double it, though technically any sentence should run concurrently with her first sentence and thus will have been spent. It is not, however, outside the realm of possibility that the charge could be changed to something that would not result in a concurrent sentence.

Richard said: “I’m not sure that I’d expect a sentence on Sunday. For sure it’s a game of cat and mouse. It’s the signal of mischief rather than the inevitability of mischief, it feels like they’re reserving the right to impose a new sentence if they want to, they’re making it clear that they can and that the British government should understand that they can, but they’re not necessarily doing it.” 

He said he would be speaking to the UK government on what it can do in terms of attending her next trial, and visiting his wife, as well as “what is going to stop Iran from holding innocent British citizens hostage”.

Richard said he had spoken to the foreign secretary last week, who was “cautiously hopeful” about his wife’s case, with Dominic Raab saying it was the “closest it’s felt for him since he’s been in office”.

Many have linked a long-standing debt running into hundreds of millions of pounds as central to the case, which has been dubbed “hostage diplomacy” by former foreign secretary Jeremy Hunt.

The UK is thought to owe Iran as much as £400m over the non-delivery of tanks in 1979, with the shipment stopped because of the Islamic revolution.

The UK continues to “explore options” to resolve that legal dispute but the prime minister’s official spokesperson said: “The UK does not and never will accept dual nationals being used as diplomatic leverage.”

Nazanin, a charity worker who was employed by the Thomson Reuters Foundation, has strongly denied the allegations that she was plotting to overthrow the Islamic Republic’s government.

She was arrested at Tehran’s Imam Khomeini Airport after taking her and Richard’s daughter Gabriella to see her parents in April 2016.