Canadian lawyers, who previously successfully sued Iran, are seeking class action status in a lawsuit on behalf of victims aboard a Ukrainian plane shot down over Tehran last month, looking for at least C$1.5 billion ($1.1 billion) in compensation.
The suit names Iran, its supreme leader, the elite Revolutionary Guards and others as defendants.
The suit alleges that the downing of the plane was "an intentional and deliberate act of terrorism."
Iranian authorities did not immediately comment on Friday, when government offices are closed.