Dominic Raab to discuss Iran threat with US's Antony Blinken during visit to London

Issues related to Iran are set to feature in talks later Monday between US Secretary of State Antony Blinken and his host in London, British Foreign Secretary Dominic Raab.

The bilateral talks come a day before the first face-to-face discussions in two years of foreign and development ministers from the Group of Seven leading industrial nations and other invited representatives. The UK holds this year's presidency of the G-7.

Mr Blinken's visit to London, his first since being appointed by President Joe Biden, comes amid mounting speculation of a prisoner exchange deal with Iran.

Prisoner exchanges are not uncommon and were a feature of the 2015 nuclear accord between Iran and leading powers. Mr Biden has indicated that he is looking to restart nuclear talks with Tehran after his predecessor, Donald Trump, pulled the US out of the agreement.

In Britain, there is particular interest in the wellbeing of British-Iranian woman Nazanin Zaghari-Ratcliffe, who was last week sentenced to an additional year in prison on charges of spreading "propaganda against the system."

British Prime Minister Boris Johnson said his government is doing what it can amid reports in Iran that Britain would pay a £400 million-pound debt to secure Mrs Zaghari-Ratcliffe's release.

"We of course make sure that we do everything we can to look after the interests of Nazanin and all the very difficult dual national cases we have in Tehran," he said.

Earlier Monday, Mr Blinken held bilateral talks with Japanese Foreign Minister Toshimitsu Motegi on an array of subjects including the coronavirus pandemic and the climate crisis, as well as raising concerns over North Korea's nuclear and ballistic missile programs.

On Tuesday, the full G-7 - Canada, France, Germany, Italy, Japan, the UK and the US - will meet along with others, including representatives from other countries, including Australia, India and South Africa.

Ahead of the gathering, German Foreign Minister Heiko Maas warned that "authoritarian states" around the world are "trying to play us against each other" and that breaches of international law have become commonplace.

"It is important that we hold our values of democracy, state of law, human rights and a global order based on rules against them, united and credibly," he said.

Before the meeting, Britain's Foreign Office said the G-7 ministers will invest $15 billion in development finance over the next two years to help women in developing countries access jobs, build resilient businesses and recover from the coronavirus pandemic.

They are also expected to sign up to new targets to get 40 million more girls into school, and 20 million more girls reading by the age of 10 in poorer nations by 2026.