British Foreign Secretary Boris Johnson says he has urged Iran to release detained dual nationals during a visit to Tehran.
Johnson met with Iranian officials in Tehran on December 9-10 in an effort to gain the release of jailed Iranian-British aid worker Nazanin Zaghari-Ratcliffe.
Johnson told the British Parliament on December 11 that he urged the release of dual nationals like Zaghari-Ratcliffe "on humanitarian grounds."
"These are complex cases involving individuals considered by Iran to be their own citizens, and I do not wish to raise false hopes. But my meetings in Tehran were worthwhile," he said. "It is too early to be confident about the outcome."
Zaghari-Ratcliffe has been held by Iranian authorities since April 2016 for allegedly plotting against Iran's government, which she denies.
Iranian Foreign Ministry spokesman Bahram Qasemi said on December 11 that Zaghari-Ratcliffe was considered an Iranian citizen and she would serve her sentence as determined by the judiciary.
Johnson said he also raised with Iranian officials "the official harassment of journalists working for the BBC's Persian service and their families inside Iran."