Iran’s Revolutionary Guards shot down the Ukraine International Airlines flight on Jan. 8, 2020 shortly after it took off from Tehran Airport in what Iranian officials said at the time was a “disastrous mistake”.

In their application to the ICJ, also known as the World Court, the four countries said Iran had violated “a series of obligations” against the so-called Montreal Convention, aimed at securing the safety of civilian air travel.

They said Iran had failed to take all practicable measures to prevent the downing of Flight PS752 and had failed to conduct an impartial, transparent and fair criminal investigation and prosecution.

Most of the people killed in the crash were citizens of the four countries, which created a coordination group aiming to hold Iran to account.

Iran says its forces accidentally shot down the Boeing 737 jet at a time when tensions were high between Tehran and Washington, and a final report issued in 2021 blamed a misaligned radar and an error by an air defence operator.

Canada at the time said the report made “no attempt to answer critical questions about what truly happened”. Ukraine called it a cynical attempt by Iranian authorities to cover up the true reasons for the crash, which it said it suspected was intentional.

(Reporting by Bart MeijerEditing by Alex Richardson and Helen Popper)