Belgian politicians who support a treaty that would permit the swap of an Iranian diplomat jailed in Belgium for Belgians held prisoner in Tehran have told the treaty's opponents that "lives are at stake".
MPs were told during a debate on Tuesday that there were serious risks to Belgians being kept in Iran if they voted against ratifying the treaty, which is set to be a first of its kind among European countries.
Vincent Van Quickenborne, Belgium's justice minister, told parliament that one unnamed Belgian had been "illegally" held on espionage charges for four months and that the risks were grave for him and others unless a deal could be cut with Tehran.
He said: "If the bill is not fully approved, the threat to our Belgian interests and certain Belgian citizens will increase . I weigh my words: there are human lives at stake. These are not my words but those of the security services."
The treaty provisionally signed with Iran in March would allow Belgium and Iran to exchange jailed nationals. The key Tehran interest is in securing a swap for Assadollah Assadi, 50, who was sentenced to 20 years in jail last year for masterminding a failed bomb attack at a rally outside Paris attended by five British MPs.
Assadi, 49, was attached to the Iranian mission in Vienna when he supplied explosives for the intended atrocity at an Iranian opposition rally in France in 2018. The Conservative MPs Bob Blackman, Matthew Offord, Theresa Villiers and Sir David Amess had attended along with Labour's Roger Godsiff. Donald Trump's lawyer Rudy Giuliani was also at the rally.
Van Quickenborne did not name the individual taken by Tehran in February but he was named in Belgian media as Olivier Vandecasteele, 44, a former aid worker, who is said to have been held in isolation since he was arrested.
The treaty in front of parliament for ratification has been criticised at home and abroad for undermining the rule of law in Belgium.
Randy Weber, a Republican congressman in Texas, tweeted that he was "shocked to find out that the Belgian government has cut a deal with the world's leading state-sponsor of terrorism and plans to send Iranian terrorists back to Iran to plot more terroristic acts".