"The FIA will not intervene in this issue," said a spokesman for the governing International Automobile Federation (FIA).
He said it would require a 'new element' for stewards to open an investigation once the results had been declared official and discounted Hamilton's post-race comments.
"A comment alleged to have been made in an internal briefing and later denied by the team itself does not constitute such a 'new element'," added the spokesman.
Hamilton said in Spa that Rosberg had admitted hitting him on the second lap during a failed overtaking manoeuvre to 'prove a point'.
The impact left Hamilton with a puncture that damaged his car and led to his eventual retirement. Rosberg damaged his car's front wing but finished second and extended his overall championship lead to 29 points.
Stewards took no action during the race and Rosberg offered a different version of events to Hamilton, saying it was merely a racing incident.
Image: Nico Rosberg
Photograph: Drew Gibson/Getty Images
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