Canada, Britain, Sweden and Ukraine on Monday formally complained to the UN aviation council in their bid to hold Iran accountable for the downing of a passenger airliner in January 2020 that killed 176 people, they said on Monday.
Most of the dead were citizens from the four nations, which created a coordination group that seeks to hold Iran to account.
"Today we have jointly initiated dispute-settlement proceedings before the International Civil Aviation Organization against the Islamic Republic of Iran for using weapons against a civil aircraft in flight," they said in a statement.
Last June the four nations said they would take their case to the International Court of Justice.
Iran says its Revolutionary Guards accidentally shot down the Boeing 737 jet and blamed a misaligned radar and an error by the air defense operator at a time when tensions were high between Tehran and Washington.
(Reporting by David Ljunggren; Editing by Richard Chang)
