The case of Nazanin Zaghari-Ratcliffe, the British-Iranian charity worker imprisoned in Tehran, is making headlines again this week after she was sentenced to another year in prison, just as she reached the end of her five-year sentence.
The 41-year-old dual national from London was first jailed in 2016 under espionage charges, which she has always denied.
The wider diplomatic backdrop is seen as critical to her release. Zaghari-Ratcliffe and her husband, Richard Ratcliffe, have long contended that she is being held by the Iranians as a bargaining chip in the name of an unpaid government debt.
But what is the debt, how are the two linked, and is the UK any closer to repaying it? Here’s what you need to know.
What is the debt?
The UK is thought to owe Iran as much as £400 million for failing to deliver Chieftain tanks, ordered by the Shah of Iran in the 1970s.
When the Shah was overthrown in 1979, Britain refused to ship over the tanks to the new Islamic Republic but kept the cash.
How is Zaghari-Ratcliffe linked to the debt?
While Dominic Raab, the Foreign Secretary, says Tehran is using Zaghari-Ratcliffe in “a cat-and-mouse game” for diplomatic leverage, the UK government has refused to formally acknowledge the link between the decades-old debt and the imprisonment of British-Iranian nationals.
This week, Boris Johnson insisted ministers were doing “everything [they] can to look after the interests of Nazanin and all the very difficult dual national cases we have in Tehran”. But, he added, their cases and the dispute over tanks are “two entirely separate issues.”
Tulip Siddiq – the Labour MP from West Hampstead representing Zaghari-Ratcliffe’s London constituency, has said: ”People seem to be being fed a false narrative that the £400m in Nazanin Zaghari-Ratcliffe’s case is a ransom. It is not. It is a historic debt that the courts (and the government) have confirmed the UK owes Iran.”
Yet some would argue that a so-called debt and a ransom amount to the same thing. Indeed, in early 2016, the US paid back its own historic military debt to Iran and in return saw the release of four Americans detained in Tehran.
According to the BBC, both Nazanin Zaghari-Ratcliffe and Anoosheh Ashoori – a 67-year-old British-Iranian engineer serving a 10-year sentence in Tehran – have been directly told by Iran’s Islamic Revolutionary Guard Corps that their cases are connected to the military debt.
Will the UK government agree to pay it back?
We don’t know exactly what’s happening behind the scenes to resolve the debt.
On Sunday, Iranian state TV announced that the UK had agreed to pay the £400m debt to see the release of Nazanin but the UK government denies this.
When James Cleverly, the Foreign Office minister, was asked about the repayment on Monday, he said: “Negotiations are ongoing. They have been for a long while, sadly, but they are ongoing.”
Asked if the talks were getting anywhere, Mr Cleverly said: “There’s a legal process tied up with this as well. Iran most recently stepped away from that legal process which has of course delayed things.”
In September 2020, Ben Wallace, the Defence Secretary, acknowledged for the first time that the UK government was actively exploring legal avenues to pay the debt. This admission came in a letter to the lawyers acting for Zaghari-Ratcliffe.
However, some British officials argue that repayment sets a dangerous precedent, and the UK cannot afford to be seen to cave in to ransom demands.
Additionally, any repayment is complicated by the fact that Iran is subject to very comprehensive sanctions.
But this latter obstacle may subside; recent negotiations have been taking place in Vienna which would involve lifting US sanctions in return for Iran complying with the nuclear deal it signed in 2015.