Liz Truss has said that she hopes a £400m debt that the UK owes to Iran could be paid back soon, after she held a call with her Iranian counterpart.

As reported by the Evening Standard, the Foreign Secretary spoke to Hossein Amir-Abdollahian on Monday (February 14), the Foreign, Commonwealth & Development Office (FCDO) confirmed.

During the call, the pair discussed the future release of British nationals held in the state and the Vienna nuclear talks, as well as the £400m debt.

The money owed relates back to the 1970s when the Shah of Iran signed a contract ordering 1,500 state-of-the-art Chieftain battle tanks and 250 repair vehicles costing £650 million from the UK.

Andover Advertiser: Nazanin Zaghari-Ratcliffe is a British national being held in Iran, and the £400m debt owed to it has been seen as a factor that could be preventing her release (PA)Nazanin Zaghari-Ratcliffe is a British national being held in Iran, and the £400m debt owed to it has been seen as a factor that could be preventing her release (PA)

An issue came up in 1979 when, with just 185 tanks delivered to Tehran, the Iranian Revolution deposed Shah Pahlavi and installed an Islamic Republic.

The UK cancelled the undelivered part of the order, and Iran wanted their money back.

It was eventually ruled by an international court that the UK owed Iran the large sum, but it has still not been paid back yet.

READ MORE - Jeremy Hunt: UK should pay £400m debt to Iran to free Nazanin Zaghari-Ratcliffe

While not confirming the discussion of the debt to Iran, the Foreign Office insisted it is committed to paying off the debt.

Both states have also claimed the outstanding debt is not related to the detention of three British-Iranians: Nazanin Zaghari-Ratcliffe, Mehran Raoof, and Anoosheh Ashoori.

Earlier this month, Ms Truss had said: “We do want to pay this debt, we recognise it’s a legitimate debt.

“But of course, there are lots of issues, which I’m sure you are quite well aware of.”