"Our military aviation campaign in Syria must not only continue, it should be intensified so that the criminals realize that retribution is inevitable," Putin said at a meeting held late on Monday.
"I ask the Ministry of Defense and the General Staff to submit relevant proposals. I am going to check the pace of this work," Putin said.
Earlier, Russia's FSB officially announced a terrorist attack as cause of the crash of the Russian Airbus A321 in Egypt's Sinai.
According to the FSB director Alexander Bortnikov, an improvised subkilogram bomb exploded on board an aircraft, which resulted in its falling apart in the air. The traces of the explosives have been found on the wreckage and belongings.