Belgium and Iran have swapped prisoners in an exchange mediated by Oman, a move criticized by an exiled Iranian opposition group as "shameful."
Oman's Foreign Ministry said the swap involving Olivier Vandecasteele, a Belgian aid worker jailed in Iran, and Asadollah Assadi, an Iranian diplomat imprisoned in Belgium, took place on May 26. Officials from Belgium and Iran both confirmed the news.
"The individuals who were released have been transported from Tehran and Brussels to Muscat today in preparation for their return to their respective countries," the ministry said in a statement.
Vandecasteele was sentenced in December to 28 years in prison by the Iranian judiciary for "espionage," a charge Brussels called "fabricated."
Belgian TV reported late on May 26 that Vandecasteele had returned to his home country after flying through Oman on a Belgian military plane.
Western countries have repeatedly charged that Iran tries to take advantage of foreign countries by taking dual and foreign nationals hostage and then using them in prisoner swaps.
During a current wave of unrest sparked by the death of a young woman after she was detained for allegedly wearing a head scarf improperly, Iranian security forces have taken some 40 foreign nationals into custody, often without revealing any charges.
Assadi was sentenced to 20 years in prison last year in connection with a plot to bomb a rally of the National Council of Resistance of Iran (NCRI), an exiled opposition group, outside Paris in June 2018. Tehran considers the NCRI a terrorist group and has called the Paris attack plot a "false flag" move by the group.
The NCRI immediately decried the swap, saying Belgium had released a "terrorist."
"The release of the terrorist...is a shameful ransom to terrorism and hostage-taking. This will embolden the religious fascism ruling Iran to continue its crimes," the Paris-based NCRI said.
Belgian Prime Minister Alexander De Croo, whose government pushed through a a fiercely criticized treaty allowing prisoner exchanges with Iran that paved the way for the swap, said Vandecasteele is expected back in Belgium late on May 26.