UK Foreign Secretary Jeremy Hunt has summoned the Iranian ambassador in London over the jailed British-Iranian aid worker Nazanin Zaghari-Ratcliffe, BBC reported on Monday.
Tehran has yet to comment on London's move, while it follows media reports, suggesting that the health of the woman had deteriorated amid her planned hunger strike.
Zaghari-Ratcliffe, who worked for the charity arm of Thomson Reuters, was arrested in April 2016 at Tehran airport and is serving a five-year prison sentence for plotting the "soft toppling" of the Islamic Republic's government.
The British foreign secretary, in turn, raised the issue with Iranian officials during his visit to the country in November 2018.
"British-Iranian dual nationals wrongly imprisoned must be freed," Hunt tweeted back in November.
The UK Foreign Office recently recommended the holders of dual UK-Iranian citizenship to avoid visits to Iran.
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