This came after US President Barack Obama told CBS radio station in a Thursday interview that there was a "possibility that there was a bomb on board," adding that Washington was taking this very seriously.
"This is just a suggestion. We said that an inquiry was continuing and it did not rule out any theories [about what caused the plane to crash]," Dmitry Peskov told reporters, commenting on Obama's statement.
He added that only the official investigation could say which of the theories looked most plausible. "We have not yet received any conclusions from the investigators," the spokesman said.
The probe into the deadly crash is being led by Egyptian experts, with the help of Russian and other foreign investigators.
The UK government was the first to suggest that the Russian airliner may have been brought down by a bomb. According to media reports, British investigators now believe that the bomb could have been planted in its hold before take-off.
The Airbus A321 came down while flying from Egypt’s resort city of Sharm el-Sheikh to St. Petersburg on Saturday, killing all 224 people on board. The air disaster is the largest in civil aviation in Russian and Soviet history.