Iran is denying allegations that a jetliner that crashed outside Tehran was brought down by an Iranian missile strike and is calling on Canada and the United States to share any information they have.

Prime Minister Justin Trudeau has said intelligence from multiple sources indicates the Ukraine International Airlines flight, carrying at least 63 Canadians, was hit by an Iranian surface-to-air missile.

Both Trudeau and U.S. President Donald Trump said a strike might have been unintentional. Ali Abedzadeh, the head of the country's national aviation department, denied those allegations today in a news conference in Tehran.

The state-run IRNA news agency quoted a Foreign Ministry spokesman as saying Iran has invited both Ukraine and the Boeing company to participate in the investigations, and is also welcoming experts from other countries' whose citizens died in the crash.

Transport Minister Marc Garneau said Thursday that Canada would offer technical assistance in the crash investigation and the Transportation Safety Board said it appointed an expert to monitor the progress of the Iranian investigation.