The two flight data recorders have been recovered from a Ukrainian passenger plane which crashed in Iran, killing all 176 people on board.
Ukraine will soon send a team of experts to Iran to investigate the circumstances of the incident.
Meanwhile, Ukrainian president Volodymyr Zelensky has warned against speculation and coming up with unconfirmed theories about the crash.
Zelensky has ordered the creation of a crisis team, managed by the country's national security agency.
The flight from Tehran to Kiev operated by Ukraine International Airlines crashed shortly after takeoff from Tehran airport in the early hours of Wednesday.
The Ukrainian Embassy in Tehran initially said the plane went down "due to an engine problem".


GCC interior ministers hold emergency meeting in Riyadh
Gunshots fired in standoff at Philippine Senate over ICC suspect
Trump lands in China for Xi summit
Israeli airstrikes kill eight people on highway south of Beirut
Philippines' Senator says arrest imminent, urges public to block ICC transfer
UK's Starmer faces biggest challenge yet as resignation threat overshadows King's Speech
Israel steps up attacks on Gaza since Iran truce, as military says Hamas rearming
Trump says he does not need China's help to end Iran war
