Canadian prime minister Justin Trudeau said evidence indicates an Iranian missile downed a Ukrainian jetliner and that the strike “may have been unintentional”.
Mr Trudeau said Canadian and allied intelligence supports that.
He declined to get into the intelligence.
Earlier, US officials said it was “highly likely” that an Iranian anti-aircraft missile downed the jetliner, killing all 176 people on board.
They suggested it could well have been a mistake.
At least 63 Canadians were on the plane.
It crashed just a few hours after Iran launched a ballistic attack against Iraqi military bases housing US troops amid a confrontation with Washington over the US drone strike that killed an Iranian Revolutionary Guard general.
At least 62 Canadians were among the 176 dead.
Mr Trudeau spoke at a news conference.