Russia has expanded the conflict with air strikes against targets in Georgia

Georgia says its forces have withdrawn from the separatist enclave of South Ossetia, and that Russian troops are now in control of the regional capital.

An interior ministry spokesman told the BBC it was not a military defeat but a necessary step to protect civilians from a "humanitarian catastrophe".

Georgia says Russia has brought an additional 10,000 soldiers across its frontiers, readying for a raid.

Earlier, Russian jets bombed a military airfield close to the Georgian capital.

There was no independent confirmation of the attack, although the BBC's Gabriel Gatehouse, who is in Tbilisi, said he had heard a loud explosion about the same time.