The United States believes that Iran mistakenly shot down the Ukrainian airliner in which 176 people were killed, CNN reported on Thursday citing several officials.
President Donald Trump has indicated the plane crash was not due to mechcal issues, adding that "somebody could have made a mistake on the other side."
"Well, I have my suspicions," said Trump when asked what he thought happened to the plane.
"I don't want to say that because other people have their suspicions," Trump said, but added, "Somebody could have made a mistake on the other side ... not our system. It has nothing to do with us."
The Boeing 737 jet operated by Ukraine International Airlines took off early Wednesday from Tehran for Ukrainian capital Kiev. Minutes after taking off it disappeared from radar.
Eighty-two Irans, 63 Canadians, and 11 Ukrainians died in the crash, which took place between the cities of Parand and Shahriar.
There were also 10 Swedes, four Afghans, three Germans and three British nationals among the victims.
Early that day, Iran had launched strikes at US targets in Baghdad in retaliation to the killing of Iran military leader General Qassem Soleim.
Meanwhile, Ukraine has opened an investigation to find out the cause of the crash. The country's officials said they are looking into multiple causes for the crash including the missile strike or terrorism.
Sweden has also joined the crash investigation on Thursday. Sweden Minister of Foreign Affairs Anne Linde told CNN that nothing was ruled out concerning the causes of the plane crash.
The UK is looking into "very concerning" reports about the Iran plane crash, a Downing Street spokesperson said.
Meanwhile, European security officials said they believe that reports suggesting that the Ukrainian airliner was shot down by an Iran surface to air missile in error are credible.
Ali Abedzadeh, the chief of Iran's Civil Aviation Orgzation, wrote in a preliminary report on the crash that both of the plane's black boxes have been damaged, with physical damage visible.
"Both devices have been damaged by fire and the accident. There is the memory parts in both devices, however, physical damage is visible on them," the report wrote.
( With inputs from ANI )