Charity worker Nazanin Zaghari-Ratcliffe remains at her parents' home in Tehran, said Tulip Siddiq, her local lawmaker in the U.K.

``I also understand that there is a British negotiating team in Tehran right now,'' Siddiq said on Twitter. ``I will keep posting updates as I get them.''

Zaghari-Ratcliffe, who has dual U.K.-Iranian citizenship, served five years in prison after being taken into custody at Tehran's airport in April 2016. She was later convicted of plotting the overthrow of Iran's government, a charge that she, her supporters and rights groups deny.

She has been held under house arrest and unable to leave the country since her release.

Zaghari-Ratcliffe's local lawyer, Hojjat Kermani, also told The Associated Press she had received her British passport. However, Kermani said she remained banned from leaving the country.

``We hope that these negotiations will be concluded soon,'' he said.