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Iran, Belgium complete prisoner swap mediated by Oman

Belgian national Olivier Vandecasteele was released from prison in Iran in an Oman-mediated exchange deal.
This photograph taken on Feb. 8, 2023, shows a large banner with a portrait of Belgian aid worker Olivier Vandecasteele.

PARIS — Iran released late Thursday Belgian national Olivier Vandecasteele, who had been detained in the country since February 2022, in exchange for the release of Iranian diplomat Assadollah Assadi, in a deal mediated by Oman. 

Vandecasteele, 42, was sentenced last January to 40 years in prison and 74 lashes over alleged espionage, while Assadi, 51, has been detained in Belgium since 2018 and sentenced to 20 years in prison for plotting a bomb attack against a rally organized by Iranian dissidents (the National Council of Resistance of Iran) near Paris.

"As I speak, Belgium's Olivier Vandecasteele is on his way to Belgium. If all goes according to plan, he'll be with us this evening. Free at last. Last night, Olivier was taken to Oman, where he was looked after by a team of Belgian military and diplomatic personnel. This morning, he underwent a number of medical examinations in order to assess his state of health and enable his return under the best possible conditions," said Belgium’s Prime Minister Alexandre De Croo on Friday morning. 

De Croo said that “Olivier spent 455 days in prison in Tehran. In unbearable conditions. Innocent,” describing his return to Belgium as “a relief for his family, friends and colleagues.”

Oman role

Oman said that the Belgian humanitarian worker had been released as part of a "mutual exchange" of two detainees between Iran and Belgium. 

Oman's Sultan Haitham bin Tariq Al Said will travel to Iran on Sunday, his first visit to Tehran since coming to power in 2020, Omani state media reported.

A statement by Omani authorities, published by Agence France-Presse, said that "the individuals who were released have been transported from Tehran and Brussels to Muscat today … in preparation for their return to their respective countries." Oman did not offer any details about its involvement in brokering the deal.

Iran's Foreign Minister Hossein Amir-Abdollahian tweeted on Friday that "Assadollah Assadi, the innocent diplomat of our country who was illegally detained in Germany and Belgium for more than two years against international law, is now on his way back to his homeland," thanking Oman for its role in securing Assadi’s release.

Legal framework

The prisoner swap became possible after the high court of Belgium upheld a treaty reached last year between Brussels and Tehran, setting a legal framework for such a deal. While welcoming the release of Vandecasteele, the small nationalist New Flemish Alliance accused the government in Brussels of caving into Tehran’s pressure and manipulations. 

"Iran understood that it needed a hostage to free diplomat Assadollah Assadi, detained in Belgium since 2018 and recognized as a terrorist. Tehran realized that for this to happen, an exchange with a Belgian had to be possible," the party told Belgium daily Le Soir. 

Two French prisoners detained in the northeast of Iran, Benjamin Briere and Bernard Phelan, were released from jail and sent back to Paris on May 12 in what was described by the sides as a humanitarian move. Four other French nationals are still detained in Iran, as is German-Iranian dual national Jamshid Sharmahd, sentenced to death in late April. According to the British Foreign Ministry, at least 40 foreign and dual nationals were arrested during the September 2022 protests in Tehran. Euronews outlet noted on May 16 that some 15 European citizens were detained in Iranian prisons.  

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