The Boeing 737 in Iran changed its course shortly after it began to crash but it is unclear at the moment what caused him to make the manoeuvre, the Ukrainian Foreign Minister Vadym Prystaiko said in a statement on Friday.
According to Prystaiko, the pilot of the crashed jet said in the last contact with the air traffic controller that the flight was going as normal.
The minister said that Kiev would request assistance from France in the investigation into the deadly incident, as the engines of the crashed aircraft were French-made.
The official added that as of now, there were not enough grounds to say that the jet crashed as a result of a terror attack.
Prystaiko emphasised that Ukraine wants the flight recorders from the Boeing to be decoded in Kiev.
"We are deciding with the Iranians where the black boxes will go; whether they would be decrypted in Iran. We want them to be decrypted in Kiev", Pristayko said at a briefing.
According to the minister, during the last conversation between pilots and air traffic controllers, the flight was carried out normally.
"We have an accurate time stamp when our pilots last contacted with controllers. We got this information today. We got full access to the conversation [recorded] not only on the black boxes that are stored on the plane, but also to the full record of the [conversation of the] Iranian air traffic controllers with our pilots. Until the last conversation, the situation on board was normal", the top diplomat added.
He noted that Iran had given Ukrainian experts access to flight recorders and fragments of the Ukraine International Airlines jet.
"We got access to parts of the aircraft and the crash site... Now our team has gained access to the black boxes, we plan to begin the reconstruction of negotiations in the near future. We also got access to the records of air traffic controllers from the flight control centre at Tehran airport and our pilots", Prystaiko said at a briefing broadcast by the Ukrainian TV channel Nash.
The Ukraine International Airlines' (UIA) Boeing 737-800 bound for Kiev crashed shortly after leaving Tehran's airport early Wednesday morning. According to official figures, 176 people - citizens of Iran, Ukraine, Canada, the UK, Germany, Sweden and Afghanistan - died in the crash