MOSCOW, August 10 (RIA Novosti) - Negotiations with Georgia will only be possible once the South Caucasus state signs a ceasefire agreement, a Russian deputy foreign minister said on Sunday.

Georgia launched a major ground and air offensive to seize control of South Ossetia on Friday, prompting Russia to send in tanks and hundreds of troops. Georgia imposed martial law on Saturday after Russian warplanes began bombarding military bases. South Ossetia's capital Tskhinvali has been largely destroyed in the violence.

"As the events at the start of August have showed, verbal statements by Georgian leaders cannot be trusted. A commitment not to use force is what Russia and the international community has insisted on over the past few years while Georgia has used various pretexts to reject it. Without this obligation being set, there can be no negotiations with Georgia," Grigory Karasin said.

Russia says around 2,000 civilians were killed in the Georgian onslaught and has branded the mass killings of South Ossetians, most of whom are Russian citizens, an act of genocide. Around 34,000 South Ossetians have fled across the border into Russia, where they are being housed in makeshift hospital camps.

According to Karasin, talks on a peaceful settlement on the South Ossetian situation are only possible if Georgian troops withdraw to their positions prior to the start of their offensive and if Tbilisi announces it will cease to use force.