Ukraine is urging Iran to return the black-box flight recorders of a Ukrainian passenger plane shot down by the Iranian forces earlier this month.
Foreign Minister Vadym Prystayko made the call on January 20 as the Iranian minister of roads and urban development was visiting Kyiv to discuss the tragedy.
Mohammad Eslami's "main task is to apologize and acknowledge what happened," Prystayko told reporters.
"We hope that we can go a little further than just political discussions and discuss practical problems. Among them in particular is the return of the black boxes," he added.
The Kyiv-bound Ukraine International Airlines Boeing 737 crashed shortly after taking off from Tehran on January 8, killing all 176 people on board. Most of the victims were Iranian and Canadian citizens.
Three days later, Tehran said the plane was shot down "unintentionally" by an antiaircraft missile during a spike in tensions with the United States.
Last week, Afghanistan, Britain, Canada, Ukraine, and Sweden -- countries whose nationals were killed in the crash -- issued a joint statement calling for a "thorough, independent, and transparent" investigation.
And on January 19, Canadian Foreign Minister Francois-Philippe Champagne reiterated Ottawa's request that Tehran hand over the black boxes to France or Ukraine "as quickly as possible."
However, the Iranian official leading the investigation into the crash appeared to backtrack on plans to send the flight recorders abroad for analysis.
Iranian media quoted Hassan Rezaeifar as saying the country might send the black boxes abroad, adding, "But as of yet, we have made no decision."
"At first they stated that they were handing them over, then the same person stated that they were not handing them over," Prystayko said. "This created some misunderstanding in Ukraine and we were starting to be asked: 'Are they being handed over or not?'"
During his meeting with Eslami, President Volodymyr Zelenskiy said that "in the matter of clarifying the circumstances of the tragedy, the Iranian party had complied with most arrangements," according to Ukraine's presidency.
A statement said Iranian experts were expected to assess Ukraine's technical ability to decode the black boxes.
"I promised the families and relatives of the victims, I promised the people of Ukraine that the truth will be established. We must know what happened," it quoted Zelenskiy as telling the Iranian minister.
The coffins of the 11 Ukrainian citizens killed in the plane crash, including nine crew members, arrived in Kyiv on January 19.