After speaking to both drivers and reviewing video evidence of the incident, the stewards deemed that Hamilton "unnecessarily impeded" the Finn at Turn 3.
Hamilton had just come out of the pits and was informed of the cars approaching, including Raikkonen.
Although the Briton tried to take evasive action when he became aware of Raikkonen approaching on a fast lap, it was not sufficient to avoid impeding the Alfa Romeo driver, who had to then abort the lap.
As a result, Hamilton, who qualified second, will drop to fifth, as well as receiving a penalty point.
"Basically one of the team's cars came by and I was braking for the hairpin, Turn 3, and I saw the other one coming," said Hamilton ahead of the investigation.
"So I got off the brakes to go straight on to get out of the way as I didn't want to meet them in the corner. I don't think I met him in the corner but I think I probably put him off, I would have thought.
"It's not ideal and I wasn't aware that that car was coming, so not the easiest."
Following the investigation he took to Instagram to admit the penalty was deserved.
"Totally deserved the penalty today and have no problem accepting it," he wrote. "Was a mistake on my behalf and I take full responsibility for it.
"It wasn't intentional," he added. "Anyway, tomorrow is another day and an opportunity to rise.
"These things are sent to try us. We all have to push through whatever it is we are up against, whether it's right or wrong, just continue to believe in yourself. We have the power to overcome obstacles even when they appear too large a task."
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