Video report by ITV News Correspondent Paul Davies
Iran has denied allegations that one of its own missiles caused the crash of a Ukrainian passenger jet and urged the US and Canada to share any information they have on the tragedy.
Western leaders said the plane appeared to have been unintentionally hit by a surface-to-air missile just hours after Iran launched around a dozen ballistic missiles at two U.S. bases in Iraq to avenge the killing of its top general in an American airstrike last week.
“What is obvious for us, and what we can say with certainty, is that no missile hit the plane,” Ali Abedzadeh, head of Iran’s national aviation department, told a press conference.
“If they are really sure, they should come and show their findings to the world” in accordance with international standards, he added.
Hassan Rezaeifar, the head of the Iranian investigation team, said recovering data from the black box flight recorders could take more than a month and that the entire investigation could stretch into next year. He also said Iran may request help from international experts if it is not able to extract the flight recordings.
US, Canadian and British officials had said it was “highly likely” that Iran shot down the civilian jetliner that crashed near Tehran, killing all 176 people on board.
They said the fiery missile strike could well have been a mistake amid rocket launches and high tension throughout the region.
The crash on Wednesday morning came just a few hours after Iran launched a ballistic attack against Iraqi military bases housing US troops in its violent confrontation with Washington over the drone strike that killed an Iranian Revolutionary Guard General Qassem Soleimani.
Canadian Prime Minister Justin Trudeau, whose country lost at least 63 citizens in the downing, said in Ottawa: “We have intelligence from multiple sources including our allies and our own intelligence. The evidence indicates that the plane was shot down by an Iranian surface-to-air missile.”
Likewise, UK Prime Minister Boris Johnson and Australian Prime Minister Scott Morrison offered similar statements.
Mr Morrison also said it appeared to be a mistake. “All of the intelligence as presented to us today does not suggest an intentional act,” he said.
At the White House, President Donald Trump suggested he believed Iran was responsible for the shoot down and dismissed Iran’s initial claim that it was a mechanical issue with the plane.
“Somebody could have made a mistake on the other side.” Mr Trump said, noting the plane was flying in a “pretty rough neighbourhood”.
Foreign secretary Dominic Raab echoed calls for an independent investigation into the plane's demise that claimed the lives of four Britons.
Speaking in Canada, he said: "We agree with the Canadian assessment that indicates that Ukrainian International Airlines flight was shot down by an Iranian surface-to-air missile."
He added: “Our view on the crash underlines why we urgently now need an independent, full and transparent investigation to establish what caused it."
Mr Trudeau attended a vigil held for the victims of the crash in Ottawa last night, laying flowers and gathering with mourners to pay his respects to those who lost their lives.
The Canadian prime minister appeared emotional as other mourners around him wept.
Previously, Tehran had ruled out allowing Boeing or US officials to take part in the probe, but in said Boeing can take part in the investigation.
The National Transportation Safety Board said it would "evaluate its level of participation" but its role could be limited by US sanctions on Iran.
Under rules set by a United Nations aviation organization, the NTSB is entitled to participate because the crash involved a Boeing 737-800 jet that was designed and built in the US.
Late on Thursday, the US House approved a measure that aims to bar any further military action against Iran without congressional approval. However, the resolution approved by the Democratic-majority House is nonbinding and no similar measure could pass the Republican-controlled Senate.
The Trump administration has announced a new wave of sanctions on Iran following this week's missile strikes by the Islamic Republic on US bases in Iraq.
Secretary of state Mike Pompeo and treasury secretary Steven Mnuchin said the new sanctions will target eight senior Iranian officials involved in "destabilising" activities in the Middle East as well as Tuesday's missile strike.
As for the airliner shot down, the US officials would not say what intelligence they had that pointed to an Iranian missile, believed to be fired by a Russian Tor system, known to NATO as the SA-15. But they acknowledged the existence of satellites and other sensors in the region, as well as the likelihood of communication interceptions and other similar intelligence.
The New York Times posted a video it said it had verified showing the moment the apparent missile struck the plane over Iran. The video shows a fast-moving object rising before a fiery explosion. An object, apparently on fire, then continues in a different direction.
A preliminary Iranian investigative report said the airliner pilots did not make a radio call for help and that the aircraft was trying to turn back for the airport when it went down.
The Iranian report suggested a sudden emergency struck the Boeing 737 operated by Ukrainian International Airlines when it crashed, just minutes after taking off from Imam Khomeini International Airport in Tehran.
Iran’s official news agency said the country is inviting Boeing experts to join the investigation into the plane crash.
Before the US assessment, Iran’s state-run IRNA news agency quoted Hasan Rezaeifa, the head of the of civil aviation accident investigation commission, claiming that “the topics of rocket, missile or anti-aircraft system is ruled out”.
Ukrainian President Volodymyr Zelenskiy said, “Undoubtedly, the priority for Ukraine is to identify the causes of the plane crash. We will surely find out the truth.”