Passengers' belongings are pictured at the site where the Ukraine International Airlines plane crashed after take-off from Iran…
Passengers' belongings are pictured at the site where the Ukraine International Airlines plane crashed after take-off from Iran's Imam Khomeini airport, on the outskirts of Tehran, Iran January 8, 2020. Nazanin Tabatabaee/WANA (West Asia News Agency…

WHITE HOUSE - Iran is denying allegations that one of its missiles shot down a Ukrainian jetliner outside Tehran and is urging the U.S. and Canada to provide any information about the crash that killed all 176 people on board.

Iranian Civil Aviation Organization chief Ali Abedzadeh said Friday at a Tehran news conference that "what we can say with certainty is that no missile hit the plane."

Abedzadeh said if the U.S. and Canada are sure about its suggestions the plane was mistakenly hit by a missile, "they should come and show their findings to the world," in accordance with world standards.

Iran's semi-official Fars news agency reported on Friday that Iran would announce the cause of the plane crash on Saturday. The news agency quoted an "informed source" saying the announcement will take place after a meeting of an Iranian commission focused on air accidents.

Earlier Friday, Iranian investigative team leader Hassan Rezaeifar said recovering information from the plane's black box fight recorders could take more than a month. He also said Iran may ask international experts for help if it is not able to extract the data.

Ukrainian President Volodymyr Zelenskiy, who spoke by phone Friday with U.S. Secretary of State Mike Pompeo, said "the missile theory has not been ruled out, but has not been confirmed yet."

The State Department said Friday Pompeo "offered the U.S. government's full assistance in the onlgoing investigation."

Ukranian Foreign Minister Vadym Prystaiko tweeted that he and Zelenskiy received unspecified "important data" about the crash after meeting Friday in Kyiv with U.S. Embassy officials and that the data would be "processed by our specialists."

Videos obtained and confirmed by major news organizations appear to show a missile fired over Tehran and striking a plane near the area where the Ukrainian jet crashed on Wednesday.

U.S. President Donald Trump is among the Western leaders who are publicly voicing suspicion that Iran may have accidentally shot down the airliner.

Somebody could have made a mistake on the other side," said Trump of Ukraine International Airlines Flight 752. "Some people say it was mechanical. Personally, I don't think that's even a question."

Iranian officials have maintained the Boeing 737-800, at an altitude of 2,400 meters, suffered a catastrophic engine failure early Wednesday, local time. Of the 176 people killed on the plane bound for Kyiv, 63 were Canadians.

On Thursday, the Iranian foreign minister's spokesman, S.A. Mousavi, tweeted, "Investigations on the cause of the Ukrainian plane crash have launched based on Int. standards & ICAO regulations; Ukraine and Boeing have been invited — as the owner & the manufacturer — to take part in it. We appreciate any country who can provide info to the Committee in charge." 

But government sources tell VOA that U.S. officials have examined satellite data and imagery leading them to believe the airliner, just after taking off from Tehran, was hit by a Russian-made surface-to-air missile after being targeted accidentally.

A U.S. official confirmed to VOA that he is confident the plane was shot down by Iran.

The crash early Wednesday occurred hours after Iran launched a ballistic missile attack on Iraqi bases housing U.S. soldiers in response to last week's U.S. drone attack that killed Iranian Quds Force commander Qassem Soleimani.

The governments of Ukraine and Canada are not accepting the initial assessment by Iran that the cause of the crash appeared to be a mechanical issue.

Citing what he called "intelligence from multiple sources," Canadian Prime Minister Justin Trudeau told a news conference Thursday that "the intelligence indicates that the plane was shot down by an Iranian surface-to-air missile."

Trudeau added, "This may well have been unintentional."

Andriy Shevchenko, Urkaine's ambassador to Canada, expressed solidarity with Canada.

Asked if Trudeau's announcement would hinder the investigation, Shevchenko Shevchenko told VOA's Ukraine service Thursday he wouldn't speculate."

I wouldn't speculate on the reasons of the crash either," he said, "but I would say that it is in the everyone's interest, including Iran to have very good, transparent and genuine investigation into this tragedy. I think that truth and only truth is something that can get us moving forward."

Sixty-three of the crash victims were from Canada, which has more than 200,000 citizens of Iranian descent. It is also popular with Iranian students for graduate and post-doctoral work.