The Russian army accused Georgia on Wednesday of blocking the return of a soldier who disappeared from his unit and said he must come back or face prosecution as a deserter.

"Alexander Glukhov must return and continue his service," Colonel Igor Konashenkov, aide to the commander of Russia's ground forces, said in a statement.

"It is self-evident that actions by Georgian authorities are the main obstacle for the Russian military serviceman's return to his motherland... Such actions push the Russian army's soldier to commit a criminal offence -- desertion."

Georgia, crushed by Russia in a brief war in August when it tried to retake its rebel South Ossetia region by force, paraded the 21-year-old soldier on Tuesday.

Dressed in jeans and trainers and eating a 'Big Mac' hamburger, Glukhov told Reuters at a McDonald's restaurant in Tbilisi he had asked for asylum in Georgia, saying conditions with Russian forces in South Ossetia were unbearable.

Moscow maintains the soldier was abducted. Russia said Georgian officials must have forced him into making statements that discredited the Russian military.

Glukhov denied being subjected to pressure.

Georgia's foreign ministry invited his parents to come to Georgia and see their son. It offered to make all the arrangements for the visit."

Georgian Foreign Minister Grigol Vashadze told reporters the soldier was free to do as he pleases.

"If this man is returned now to Russia, he is under threat of being accused of desertion and treason, and simply thrown in jail," he said.

Konashenkov said Glukhov's commander had no complaints about his service and that he had not committed any misdeeds.

"He served for more than a year and would have demobilised in four months," he said.

An officer responsible for Glukhov's hometown of Sarapul in Udmurtia met with his parents to assure them that no effort was being spared for their son's return to Russia, Konashenkov said.