The International Criminal Court (ICC) is to investigate alleged war crimes committed during the brief war between Georgia and Russian-backed rebels in South Ossetia in 2008.
It will be the first time the court has carried out an inquiry outside Africa.
In a statement, judges said there was reason to believe crimes against humanity, including murder and persecution, had been committed during the five-day conflict.
The statement said the probe would also cover attacks on peacekeepers, destruction of property and pillaging.
It added there were “no substantial reasons to believe that an investigation would not serve the interests of justice”.
She said she had evidence that between 51 and 113 ethnic Georgians were killed by South Ossetian troops during a forcible displacement campaign, possibly also involving Russian forces.