He made the remarks during second telephone conversation with his Ukrainian counterpart Volodymyr Zelensky over the past two days when he referred to a statement by the General Staff of Armed Forces and official declaration of results of investigations on disaster, adding that the statement announced that human error caused the accident and those involved in the disaster will be delivered to the judicial authorities.
Noting that collaboration for completing research will continue, he pointed out that Judiciary will soon start measures to deal with the case.
"We in Iran and You in Ukraine should try to make the catastrophe tolerable to the two nations and relieve sufferings," he said, he will soon dispatch a representative to Kiev to officially express grief and regret of the Iranian nation and government.
President Zelensky, for his part, condoled with Rouhani over the disaster, saying that your today's statement was very significant for Kiev.
He also hailed Iran's lawful behavior and effective cooperation under the difficult conditions.
Zelensky also hoped that investigations by the Iranian and Ukrainian experts would continue to be able to end the investigations based on the legal protocols.
All 176 passengers on board the Ukrainian Boeing 737 were killed after it crashed shortly after departure from Tehran's main international airport early Wednesday.
There were 167 passengers and nine crew members on flight PS-752 that burst into flames mid-sky and crashed into ground near Parand, a city southwest of Tehran.
Among the victims were over 140 Iranian nationals and 32 from other countries, including Ukraine, Sweden, Germany and Britain.
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