Ukraine demands punishment, compensation for airliner downed by Iran
"We expect Iran... to bring the guilty to the courts," the Ukrainian leader wrote on Facebook, calling also for the "payment of compensation" and the return of remains.
Tehran admitted on Saturday that it accidentally downed the Ukraine International Airlines (UIA) plane, killing all 176 people on board on Wednesday, shortly after launching missiles at bases hosting US forces in Iraq.
"We hope the inquiry will be pursued without deliberate delay and without obstruction," Zelensky added
He urged "total access" to the full inquiry for 45 Ukrainian experts, and in a tweet also sought an "official apology".
Iranian President Hassan Rouhani said earlier on Saturday that Tehran "deeply regrets this disastrous mistake".
UIA chief Yevhenii Dykhne also posted on Facebook, saying: "We never had any doubt that our crew and our plane could be the cause of this terrible catastrophe. They were the best."
Ukraine said on Friday its experts dispatched to Iran had been granted access to the flight's black boxes, debris from the plane, the crash site and to recordings of conversations between the pilot and the airport control tower.
Iran's official IRNA news agency published a statement from the military saying the Boeing 737 was mistaken for a "hostile plane" at a time when threats were at the highest level.
Tehran has invited the United States, Ukraine, Canada and others to join the crash investigation.
The majority of passengers on UIA Flight PS752 from Tehran to Kiev were Iranian-Canadian dual nationals but also included Ukrainians, Afghans, Britons and Swedes
Many in Kiev have compared the crash to the 2014 downing of Malaysian Airlines MH17 killing 298 people over eastern Ukraine where pro-Russian separatists are fighting government forces.
Moscow has denied the findings of international investigators that a Russian BUK misile hit the Malaysian flight.
"Iran has shown itself more civilised than Russia," pro-western Ukraine MP Volodymyr Ariev wrote on Facebook.
"Tehran has admitted its guilt in three days while Russia continues to try to get out of it."