Iran has summoned the Swedish Ambassador after Stockholm granted citizenship to Dr Ahmad Reza Jalali, sentenced to death on charges of spying for Israel.

Foreign Ministry Spokesman Bahram Qassemi said Helena Sangeland was served with a note of the Islamic Republic’s “strong protest” over the “uncommon, questionable, and unfriendly” nationalization of the doctor.

Jalali is a physician and researcher, specializing in disaster medicine, affiliated with the Karolinska Institute near Stockholm. He was detained in April 2016 while he was on an official academic visit hosted by Tehran University, and eventually convicted behind closed doors by a Revolutionary Court. Iran’s Supreme Court upheld the death sentence in December, despite Swedish protests.

The regime has never presented the evidence against Jalali, but has declared his “confession” of working for the Israeli intelligence service Mossad and complicity in the murder of Iranian nuclear scientists. In an audio, Jalali said his statement, broadcast in December on State TV, was obtained under duress.

On Saturday, Stockholm confirmed Jalali’s citizenship. Qassemi reponded that Iran still considers Jalali as an Iranian national: “No country is allowed to interfere in the Islamic Republic’s internal affairs under any circumstances.”