Russia could redeploy its forces in Syria "in a few hours", Russian President Vladimir Putin, days after his surprise announcement that Russia would be scaling back its military presence in the country.

"Of course, if required Russia will be ready in just a few hours to increase its forces in the region to a size that is adequate to meet the situation and use our full arsenal of options," Putin said in a speech during a ceremony at the Kremlin for Russian military personnel returning from Syria. "We don't want to do that, military escalation is not our preferred route, and so we are hoping that all sides will show common sense and that both the authorities and the opposition will adhere to the peace process."

Russia will retain its base in Latakia, from where it has launched hundreds of airstrikes against Syrian rebel groups fighting to oust Syrian president Bashar al-Assad, Putin said announcing the partial withdrawal on Monday, 14 March. He also said its advanced S-400 air defence system would remain in place.

Putin said on Thursday that the smaller force he had left in place was sufficient to ensure continued progress for the forces of Assad, adding that airstrikes would continue against Jabhat al Nusra and Isis. "I'm sure that we will see new and serious successes in the near future," Putin said, adding that he hoped that Syrian forces would soon be able to retake the ancient Syrian city of Palmyra from jihadist group Isis (Daesh).

"I hope that this pearl of world civilisation, or at least what's left of it after bandits have held sway there, will be returned to the Syrian people and the entire world," Putin said.

The announcement comes as Isis published footage of what is claims is the dead body of a Russian military adviser who was killed by militants near Palmyra. The film shows the man's body, as well as military equipment allegedly belonging to him. In recent days Russia has supported Syrian government forces battling Isis near Palmyra with air strikes.

When Russia entered the conflict officials claimed the chief target would be Isis, however most airstrikes were conducted against moderate rebel groups, some of which were backed by the CIA. Peace talks have begun this week between the Syrian government and opposition groups. Putin praised "restraint, sincere desire for peace and for his readiness for compromise and dialogue", and said that the withdrawal had been agreed with the Syrian president beforehand. "You, soldiers of Russia, opened up this pathway to peace," he told the audience.

During the speech Putin said Russia had spent 33bn roubles (£336m) on the five month mission, and added four servicemen had been killed.