Washington  - The United States is sending an envoy to help bring about a ceasefire in the escalating conflict in Georgia's breakaway South Ossetia region, the US State Department said Friday.

Secretary of State Condoleezza Rice had also been in contact with a number of foreign officials to seek an end to the hostilities, which threatened to turn into a full-out war between Russia and Georgia.

Georgian President Mikheil Saakashvili earlier said Russian troops had invaded his country, after Georgia sent forces into South Ossetia and claimed to have taken control of the capital.

"We support Georgia's territorial integrity and we call for an immediate ceasefire," State Department spokesperson Amanda Harper told Deutsche Presse-Agentur dpa.

The US was working on "mediation efforts" to help secure an end to the hostilities, Harper said.

The United Nations Security Council scheduled another emergency meeting Friday afternoon in New York, after failing Thursday night to agree on a response to the escalation of violence. (dpa)