Iran has sent the black box of a Ukrainian passenger plane which was accidentally downed in Tehran earlier this year to France.
All 176 people on board were killed when the plane was hit by two missiles shortly after take-off on 8 January.
Iran's deputy foreign minister said the black boxes were taken to Paris on Friday and would be read on Monday.
Iran initially denied responsibility for the incident, which came amid heightened tensions with the US.
But the country admitted fault days later, after Western intelligence officials said evidence pointed to Iranian involvement.
Tehran said the Ukraine International Airlines flight had been mistaken for a cruise missile, in what President Hassan Rouhani described as an "unforgivable mistake".
Iran's air defences had been on high alert at the time. Hours before the crash, the country had fired ballistic missiles at two US bases in Iraq in retaliation for the killing of top Iranian general Qasem Soleimani by a US drone strike in Baghdad.