The US vice-president, Dick Cheney, used his morale-boosting visit to Georgia today to condemn Russia for what he says is an "illegitimate, unilateral attempt" to change the country's borders by force.
Cheney was speaking at a news briefing in Tbilisi with the Georgian president, Mikhail Saakashvili.
In words which are likely to exacerbate tensions in the region, he said: "After your nation won its freedom in the Rose revolution, America came to the aid of this courageous young democracy," he said.
"We are doing so again as you work to overcome an invasion of your sovereign territory and an illegitimate unilateral attempt to change your country's borders by force, that has been universally condemned by the free world.
"Russia's actions have cast grave doubt on Russia's intentions and on its reliability as an international partner - not just in Georgia but across this region and, indeed, throughout the international system."
Cheney also assured Georgia's president that the US supports the nation's efforts to join Nato, although Saakashvili says he is committed to a peaceful resolution of its disputes with the breakaway regions of South Ossetia and Abkhazia.
Russia has recognised both as independent nations and earlier this week dismissed Saakashvili as a "political corpse", whose leadership it did not recognise.
Dick Cheney's visit comes a day after the White House announced a $1bn (£500m) economic aid package for the country, which was ravaged by last month's war with Russia.
Cheney arrived after a trip to neighbouring Azerbaijan, where he said the US had a "deep and abiding interest" in the region's stability.
Azerbaijan is the starting point for a major oil pipeline that crosses Georgia and ends in Turkey - the only energy export route from central Asia westwards that does not pass through Russian territory.
Yesterday, the International Monetary Fund announced that Georgia was to receive a $750m (£422m) loan.
The Russian president, Dmitry Medvedev, has accused the US of helping Georgia build its armed forces, and criticised its decision to send humanitarian aid to Georgia aboard military ships.
Faced with a chorus of international calls for Russia's isolation as a result of the war, Medvedev said Moscow did not fear being expelled from the G8 group of rich nations, nor did it fear Nato cutting ties with his country.
Earlier this week, EU leaders agreed to suspend talks on a new partnership agreement with Moscow until Russian troops withdrew from Georgia, but they did not threaten sanctions.
Cheney will end his tour of the region in Ukraine later today.
