Earlier reports from Iranian state media had said 180 people were on board Flight PS752.
Eighty-two Iranians, 63 Canadians, and 11 Ukrainians died in the crash, according to a tweet from Ukrainian foreign minister Vadym Prystaiko.
There were also 10 Swedes, four Afghans, three Germans and three British nationals among the victims, he said.
Thirteen former students of Sharif University of Technology, in Tehran, were among those killed, according to a tweet from the university.
The Ukrainian Embassy in Tehran replaced its previous statement saying terrorism or rocket attacks had been ruled out as causes of the plane crash.
“Information on the causes of the plane crash is being clarified by the commission,” it said.
Iran’s semi-official news agency ISNA previously reported the crash was due to technical difficulties. Iran’s Civil Aviation Authority said it had launched an investigation.
Ukrainian President Volodymyr Zelensky said in a Facebook post that he would cancel the rest of his current trip to Oman and would return to Kiev due to the crash. “My sincere condolences to the families and loved ones of all passengers and crew members,” Zelensky said.
Emergency crews were dispatched to the crash site but could not assist because the area was ablaze, said Pirhossein Koulivand, the head of Iran’s Emergency Medical Services. Koulivand told state-run media outlet IRINN that the crash site is between the cities of Parand and Shahriar.
Ukraine International Airlines refused to comment on the cause of the crash.
However airline president Yevhenii Dykhne did say that Tehran airport is “not a simple airport.”
A pilot requires “several years” of training at the airport, said Dyknhe at a press conference in Kiev.
“It is impossible that there were mistakes by the crew,” he said.
The cockpit voice recorder and flight data recorder from the plane, commonly known as black boxes, have been found, Iranian state broadcaster IRIB reported, citing the Tehran prosecutor.
They could provide crucial evidence about what happened to the plane leading up to the crash.
A Boeing spokesperson told CNN they are “aware of the media reports out of Iran and we are gathering more information.”
The crash takes place just days before the company’s new CEO David Calhoun will formally take the job. Calhoun replaces Dennis Muilenburg, who was ousted in December after Boeing’s disastrous year.
The American aviation giant is still reeling from the aftermath of two 737 Max crashes, which killed 346 people. The Max has been grounded worldwide since March, and the company has struggled with delays and other issues in its bid to get the planes back in the air.
This is a developing story and will be updated.