Top UK Diplomat Due in Tehran

British Foreign Secretary Boris Johnson is to visit Tehran today to hold discussions on a wide range of issues from bilateral relations to regional security.

Foreign Ministry Spokesman Bahram Qasemi made the announcement in a statement on Friday, ISNA reported.

"In this trip, the course of bilateral ties, particularly in the economic sector, expansion of trade ties, regional issues and international developments will be discussed," he said.    

Johnson, who will meet his Iranian counterpart Mohammad Javad Zarif, is also expected to talk about the future of the 2015 nuclear deal.

The visit to Tehran, the first by Johnson and the third by a British foreign secretary since 2003, follows a thaw in relations after the deal lifted international sanctions against Tehran in January 2016.

The two sides will probably exchange views on how to overcome a series of stumbling blocks preventing a big improvement in bilateral ties, including banking restrictions on Iranian companies and individuals operating in the UK.

A UK Foreign Office spokesman said on Friday Johnson's discussions in Tehran will also include his attempt to free an Iranian-British dual national Nazanin Zaghari-Ratcliffe jailed in Iran over security charges, the Daily Mail reported.

Zaghari-Ratcliffe claimed to be a charity worker affiliated with the Thomson Reuters Foundation, was arrested in April 2016 just before he leaves Iran.

She is now serving a five-year jail sentence for clandestine efforts to spread propaganda against the Iranian government.

Zaghari-Ratcliffe is due to face fresh charges in court this week, which could lead to several more years in prison. Her case drew considerable attention last month, after Johnson suggested she was training journalists in Iran, contradicting claims by the foundation that she was simply on holiday visiting relatives.

His comments confirmed charges by the Iranian judiciary that Zaghari-Ratcliffe was teaching people how to secretly prepare anti-government content and send them to the Persian service of the British state-run BBC news agency. Johnson has apologized for his "slip of the tongue", vowing to make every effort to secure the release of Zaghari-Ratcliffe.

Iran has signaled it could agree to measures to improve Zaghari's conditions on humanitarian grounds.