OTTAWA — Ukraine will help Canada participate in the Iranian-led investigation of Wednesday’s plane crash near Tehran that killed dozens of people from their countries, says the Ukrainian envoy in Ottawa.

“The investigation on the ground is conducted by Iran, and Ukraine will of course contribute,” Andriy Shevchenko, Ukraine’s ambassador to Canada, said in an interview. “We’re ready to do everything we can to help the investigation. We hope that the Canadian offer of contribution into the investigation will be recognized and appreciated.”

The Ukraine International Airlines Boeing 737-800, bound for Kyiv, crashed shortly after taking off from the Iranian capital, killing all 176 people on board. Ukraine’s Foreign Minister Vadym Prystaiko said the plane was carrying 63 Canadians, 82 Iranians, 11 Ukrainian passengers and crew, 10 Swedes, four Afghans, three Germans and three Britons.

The Ukrainian offer is significant because Canada broke diplomatic relations with Iran in 2012, shuttering its Tehran embassy and expelling its diplomats. The government cited Iran’s support of terrorism and concerns for the safety of its diplomats. Canada has also been a vocal critic of Iran’s human-rights record, including at the United Nations.

Prime Minister Justin Trudeau said Canada will work with its international partners to investigate the cause of the plane crash thoroughly. Transport Minister Marc Garneau said on Twitter that Canada would offer technical assistance in the crash investigation.

“Our minister of foreign affairs had a phone conversation with the Iranian minister of foreign affairs, so we have established contact on this. We also have our Ukrainian Embassy on the ground in Tehran,” said Shevchenko.

“It is heartbreaking. We have been such close friends with Canada and share so many good things. Now we will have to walk through this pain together.”

Ukraine has determined that a “substantial portion” of the 63 Canadians had booked onward tickets on a flight to Toronto and were not stopping in Kyiv, said Shevchenko.

Others aboard were likely bound for Canada but aren’t citizens.

Ukraine officials are also working closely with the Iranians to identify all the victims and repatriate their remains, Shevchenko added. The Ukraine government has dispatched two planes to Iran to help with that grim task.

Watch: 176 people killed in Iran plane crash. Story continues below.

The Conservative defence critic says he doesn’t want the Iranian government to block access to investigators from Canada or any other countries affected.

“I would encourage the Iranian regime to co-operate with the international investigation, and in particular allow Canada, Ukraine and the other nations who lost citizens on that flight to be involved in that investigation, regardless of the regional tensions right now and the politics surrounding the recent attacks,” Tory MP James Bezan said in an interview.

U.S. Secretary of State Mike Pompeo said in a statement said the United States wants “complete co-operation with any investigation into the cause of the crash.”

The crash occurred just hours after Iran launched missile attacks on bases in Iraq where American troops are stationed. Iran said the attacks were retaliation for the American killing of a top general near Baghdad last week.

The Iranian military disputed any suggestion the plane had been hit by a missile, and Iranian aviation authorities said they suspected a mechanical problem brought down the 3 1/2-year-old Boeing 737. Ukrainian authorities initially said it appeared mechanical failure was to blame, but later walked that back, saying nothing had been ruled out.

“Iran’s retaliation last night was a needless attack. But regardless, this (crash) is a human tragedy that goes beyond anything that we were expecting in the fallout from the last few days,” said Bezan.

“Families deserve to get a full report on exactly what happened,” he added. “I don’t think we can speculate on the cause of the crash, but answers have to be forthcoming. I’m sure families would be devastated if Iran blocked access of international investigators from helping out with the full investigation into what caused the crash.”

NDP Leader Jagmeet Singh said on Twitter: “These families deserve clear answers, but whatever the cause, this is devastating.”

Foreign Affairs Minister Francois-Philippe Champagne and Garneau are reaching out to their international counterparts, Trudeau said.

“Our government will continue to work closely with its international partners to ensure that this crash is thoroughly investigated, and that Canadians’ questions are answered,” Trudeau said in a statement.

“Today, I assure all Canadians that their safety and security is our top priority. We also join with the other countries who are mourning the loss of citizens.”

Champagne described the situation as “extremely fluid.”

“I have been in touch with my Ukrainian counterpart, and will continue to speak to all relevant authorities. The government of Canada is committed to working closely with international partners regarding any possible investigation,” the minister said in a statement.

Trudeau also offered condolences to the loved ones of those who died.

“This morning, I join Canadians across the country who are shocked and saddened to see reports that a plane crash outside of Tehran, Iran, has claimed the lives of 176 people, including 63 Canadians,” said Trudeau.

“We also join with the other countries who are mourning the loss of citizens.”

Conservative Leader Andrew Scheer also offered his condolences on Twitter, calling it a “horrific tragedy.

“Today is a sad day four our country,” Scheer wrote.

Richard Mills, the acting U.S. ambassador to Canada, also offered his condolences to Canadians.

“We join the global community in mourning the loss of all those killed in this tragic incident,” he said in a statement.

With files from the Associated Press.

This report by The Canadian Press was first published Jan. 8, 2020.