Ukraine's president says a leaked audio recording proves the Iranian government knew immediately that it had shot down that Ukrainian jetliner in Tehran last month, killing everyone aboard, despite denying involvement for days.
President Volodomyr Zelenskiy made the comments during a visit by Turkish President Tayyip Erdogan.
It comes a day after a Ukrainian news channel aired what appears to be the flight control tower talking to another passenger jet, an Iranian one, shortly before the incident.
The pilot can he heard saying that he saw what appears to be a missile in the air.
The tower tries to contact the Ukrainian jet, with no response.
The pilot then reports seeing a huge explosion.
One-hundred seventy six people were killed.
The Iranian government is decrying the leak. It says that as a result it will stop sharing evidence with Kiev investigators.
Ukrainian International airways flight 752 is said to have been shot down accidentally, during Iran's standoff with U.S.-led forces last month.
Iran had launched missile strikes on Iraqi bases hours before.
Iran says it worked as quickly possible to determine the cause of the incident.
The Iranian commander who first acknowledged the missile strike has said that he informed authorities the same day.
Zelenskiy also says that Iran offered to pay $80,000 to each family of the victims.
It's not enough, he says, and they still haven't received the black boxes.