BEIRUT (Reuters) – Iran will treat a British-Iranian aid worker as an Iranian citizen and she will serve her sentence as determined by the judiciary, Iran’s foreign ministry spokesman said on Monday.

British Foreign Secretary Boris Johnson discussed Nazanin Zaghari-Ratcliffe’s case with Iranian officials after flying to Tehran over the weekend to try to seek her release.

“One of the issues that Johnson brought up in Tehran was the issue of Ms. Zaghari,” Iranian foreign ministry spokesman Bahram Qassemi was quoted by state media as saying.

“With regard to her dual nationality, from our point of view of course she is Iranian and she has been sentenced by the judiciary and she will serve the period of her sentence.”

Britain says Zaghari-Ratcliffe was visiting family on holiday in April 2016 when she was jailed by Iran for attempting to overthrow the government.

Johnson said he urged the release of dual nationals.

“I urged their release, on humanitarian grounds, where there is cause to do so,” Johnson told the British parliament.

“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 is not the only dual national being held in Iran, but her case has taken on political significance in Britain after Johnson said last month that she had been teaching journalists in Iran, which her employer denies. Johnson later apologized.

Opponents have called for him to resign if his comments lead to her serving longer in prison.

Qassemi said the Iranian foreign ministry would follow up on Zaghari-Ratcliffe’s case but said that it was ultimately a matter for the judiciary.

A project manager with the Thomson Reuters Foundation, Zaghari-Ratcliffe was sentenced to five years in prison after being convicted by an Iranian court of plotting to overthrow the clerical establishment. She denies the charges.

The Thomson Reuters Foundation is a charity organization that is independent of Thomson Reuters and operates independently of Reuters News. It says Zaghari-Ratcliffe had been on holiday and had not been teaching journalism in Iran.

Johnson also said he raised with Foreign Minister Mohammad Javad Zarif what he called “the official harassment of journalists working for BBC Persian and their families inside Iran.”

The BBC has called on Iran to reverse a court order which it said effectively froze the non-liquid assets of 152 staff, former staff and contributors in Iran.

(Reporting By Babak Dehghanpisheh; Additional reporting by Andrew MacAskill and Guy Faulconbridge in London; Editing by William Maclean and Peter Graff)