Last week, an Iranian war veteran fell into coma, suffering respiratory problems after he was exposed to mustard gas some three decades ago.

Hadi Kazemnejad is one of up to 1,000,000 Iranians who were exposed to chemical weapons used by Saddam Hussein during his war on Iran, officials say.

Reports say some 10,000 to 20,000 were killed and 100,000 of the victims who survived have come down with various illnesses.

Cases like Kazemnejad's point to the long-term damage of chemical warfare, provoking Tehran to condemn any sort of chemical attacks in Syria ever since the crisis-hit state came under chemical attacks over the past months.

In a Facebook posting Iran's new foreign minister, Mohammad Javad Zarif, condemned the use of chemical weapons, regardless of who did it.

The posting received more than 2,000 responses from Iranians at home and abroad.

The newly elected Iranian President Hassan Rouhani has applauded Damascus for joining the UN anti-chemical weapons treaty in a US-Russia deal that would bring Syria’s chemical weapons under the UN watch.

MRKD/SHI