Open this photo in gallery Photographs of student victims of a Ukrainian passenger jet which crashed in Iran are seen during a vigil at University of Toronto student housing, on Jan. 8, 2020. CHRIS HELGREN/Reuters

In a rare communication between Ottawa and Tehran, Foreign Minister François-Philippe Champagne called his Iranian counterpart Mohammed Javad Zarif late Wednesday and asked him to “quickly” allow Canadian officials into Iran so that they can help investigate why a Ukraine International Airlines plane crashed near Tehran, resulting in the death 63 Canadian citizens.

The conversation was rare because Canada and Iran have not had formal diplomatic ties since 2012, when Ottawa closed its embassy in Tehran – citing unspecified security threats – and expelled Iranian diplomats.

A read-out of Wednesday phone call provided by Global Affairs Canada said Mr. Champagne and Mr. Zarif “exchanged condolences for the victims of the crash of Ukraine International Airlines flight 752 from both their countries” and that Mr. Champagne had “stressed the need for Canadian officials to be quickly granted access to Iran to provide consular services, help with identification of the deceased and take part in the investigation of the crash.

“Minister Champagne said that Canada and Canadians have many questions which will need to be answered.”

A report carried by Iran’s semi-official Tasnim news agency said only that Mr. Zarif and Mr. Champagne had “exchanged views on the deadly crash of a Ukrainian airliner near the Iranian capital and issues of mutual interest” during their call.

On Thursday, Prime Minister Justin Trudeau said intelligence “indicates that the plane was shot down by an Iranian surface-to-air missile.”

The Ukrainian plane crash in Iran: What we know so far

Earlier Thursday, a report said Iran’s civil aviation authority – in an online statement – has invited Canadian investigators from the Transportation Safety Board to join a growing team probing the plane crash outside Tehran that killed 138 people believed bound for Canada.

UIA flight 752 caught fire and fell from the sky shortly after taking off from Imam Khomeini International Airport early Wednesday, killing all 176 people on board. One hundred and thirty-eight of the passengers were headed to Canada after connecting in the Ukrainian capital of Kyiv. Many were students or staff at Canadian universities who had been in Iran for the holiday season.

The call between the foreign ministers – which took place late Wednesday for Mr. Champagne, early Thursday in Tehran – came as Iranian investigators announced their initial finding that plane had caught fire due to a technical failure and was trying to return to the airport when it crashed.

However, Iran has yet to give foreign investigators access to the so-called “black boxes” – which contain data and cockpit communications – that were recovered from the scene of the disaster. The initial findings were unlikely to end calls for Iran to allow international teams access to the evidence.

The Iranian report said both of the plane’s black boxes had been recovered, though they had been damaged and some parts of their memory had been lost. The report also ruled out laser or electromagnetic interference as causes of the crash.

On Thursday, Reuters reported that Ukraine President Volodymyr Zelenskiy, in a phone call with Iranian counterpart Hassan Rouhani, discussed the investigation into the crash. “Hassan Rouhani stressed that Iran would provide the Ukrainian expert group with prompt access to all the necessary data,” Mr. Zelenskiy’s office said in a statement.

The disaster occurred early Wednesday morning in Tehran, just hours after Iran’s Revolutionary Guard had fired several volleys of ballistic missiles at two U.S. military bases in neighbouring Iraq. There was no immediate evidence of a connection between the hostilities and what happened to Flight 752.

A team from Ukraine, which has opened a criminal investigation into the crash, arrived in Tehran on Thursday, and was waiting for permission to access the site. Oleksiy Danilov, secretary of Ukraine’s Security Council, said officials had several working theories regarding the crash, including the possibility that the plane had been struck by a missile.

“A strike by a missile, possibly a Tor missile system, is among the main [theories], as information has surfaced on the internet about elements of a missile being found near the site of the crash,” he said. A Tor missile is a Soviet-made anti-aircraft weapon known to be in the Iranian arsenal.

Mr. Danilov did not say where on the Internet he had seen the Tor missile theory. Another idea the Ukrainians say they would like to investigate is the possibility Flight 752 collided with a drone.

Mohammad Eslami, Iran’s minister of road and urban development, called for an end to speculation that the disaster – which occurred hours after Iran fired a barrage of ballistic missiles at U.S. military targets in Iraq – was a result of the military activity that night.

“There are rumours that a terrorist attack, explosion or shooting at the plane may have caused the incident, but they are not true. Technical failure has been the cause of the incident," Mr. Eslami told reporters in Tehran. “Had the rumours been true, the plane must have exploded up in the air, but that has not happened, because the plane caught fire due to technical failure. That first caused its communications and control systems to stop working, and subsequently resulted in its crash.”

Iranian media have repeatedly pointed to the fact that the Boeing 737-800 is part of the same aircraft family as the Boeing 737 Max, an aircraft that has been grounded worldwide since March after two deadly accidents. The Boeing 737-800 is an older model. Unlike the Max, which has problems with a flight-control system, the 737-800 has been seen as a reliable workhorse.

Iran has said it will not allow U.S. participation in the investigation, and will not hand the black boxes over to Boeing.

Not since the Air India disaster of 1985, when 280 Canadians were among the 329 killed, have so many Canadians lost their lives in an aviation disaster.

Until it suspended its Tehran service in the wake of the disaster, Ukrainian Airlines had offered one of the cheapest connections between Toronto and Tehran.

Canada’s lack of a diplomatic presence in Tehran looms as a major impediment to offering consular support to victims of the disaster.

Speaking at a press conference Wednesday in Ottawa, Prime Minister Justin Trudeau said many countries had offered Canada their assistance, including Italy – which represents Canadian interests in Tehran in the absence of an embassy – as well as Australia and France. “Canada will be part of that investigation, not only because we have the expertise, but because we have suffered such a significant loss of lives for our citizens,” Mr. Trudeau said.

Flight 752 crashed less than four minutes after taking off from Imam Khomeini International Airport at 6:12 local time on Wednesday morning. Data on the flight radar website show the plane taking off as normal, and rising to an altitude of 7,925 feet before it suddenly stopped broadcasting its co-ordinates.

Amateur videos posted on social media showed what appeared to be a small fire in the sky, followed by a larger fire and then the bang of an explosion.

Initial statements from Ukraine about what happened to the flight were contradictory. In a statement on its website, the Ukrainian embassy in Tehran initially said the crash was due to engine failure. However, the statement was later deleted and Ukrainian International Airlines subsequently said it was still probing the cause of the crash and cancelling all flights to Tehran in the meantime.

UIA said the plane that crashed Wednesday had been built in 2016, was in “good condition,” and had last been serviced just two days before the disaster. UIA said both pilots on Flight 752 had thousands of hours’ of experience flying Boeing 737 aircraft.

Transport Minister Marc Garneau said at the news conference with Mr. Trudeau that there could be “multiple reasons” for the crash.

“We cannot speculate at this point as to the cause of the tragic air accident,” Mr. Garneau told reporters. “The indications we have from satellite data … suggest that it took off in a normal fashion. However, we lost contact with it, suggesting that something very unusual happened.”

Canadian aviation officials have reached out to Ukraine to offer their expertise in probing the crash, Mr. Garneau said. But he conceded that they are missing key information that could shed light on the cause of the crash, including the black boxes. One of the boxes, he said, contains a recording of the conversation between the pilot and the control tower.

"We’re scrambling to get as much information as we can, but it’s going to take a little while to get answers,” Mr. Garneau said.

Asked by reporters if he could categorically say the plane had not been shot down, Mr. Trudeau responded: “I cannot. It’s too early to speculate.”

With reporting by Karen Howlett and Joe Friesen in Toronto, Geoffrey York in Jerusalem and Steven Chase in Ottawa

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