President Bush says the fighting must stop.
"I am deeply concerned about the situation in Georgia," he said. "The United States takes this matter very seriously."
Hesays he is particularly troubled by the fact the conflict is spreadingto other parts of Georgia - a reference to Russian bombings beyond theborders of South Ossetia.
"The violence is endangering regional peace," said President Bush. "Civilian lives have been lost and others are endangered."
SouthOssetia's autonomous status was abolished by the Georgian government in1990, then reinstated in 1992. The current government in Tblisi hasvowed to bring it back into the fold and on Thursday launched amilitary operation to do just that.
But South Ossetia has strongties to Moscow, which supports the separatist movement. When Georgiasent its forces in, the Russians responded by sending in more troopsand bombers.
President Bush says all sides need to step back, stop hostilities, and work with mediators to resolve the conflict.
"Georgiais a sovereign nation and its territorial integrity must be respected,"he said. "We have urged an immediate halt to the violence and astand-down by all troops."
White House officials say PresidentBush re-enforced the U.S. position in separate conversations withRussian President Dmitri Medvedev, and Georgian President MikhailSaakashvili. In his brief comments to reporters in Beijing, Mr. Bushcalled on Russia to stop bombing and start cooperating with peaceefforts.
"Russia needs to support these efforts so that peace can be restored as quickly as possible," he said.
Russian officials claim 1,500 lives have been lost and tens of thousands have fled to bordering North Ossetia in Russia.
The feud between Russia and Georgia has pitted two former Soviet Republics against each other, drawing international concern.
TheUnited States, the European Union and the Organization for Security andCooperation in Europe announced Friday they were sending a delegationto Georgia in hopes of securing a cease-fire.
The U.N. Security Council is expected to meet again Saturday to discuss the crisis.