Moscow/Tbilisi  - Russia military forces turned up the pressure on their Georgian opponents on Tuesday as international diplomats scrambled to bring a ceasefire to the widening war in Ossetia.

The sharpest combat as of Tuesday morning was in the Kodori Gorge in Georgia's west, where Abkhazia infantry and armour began an attack on Georgian defences, according to a Georgian government report.

The six-day-old Ossetia war has sparked fighting between Georgia on two fronts, in Georgia's separatist province South Ossetia, and on the border between Georgia and its second separatist province Abkhazia.

Russian armoured columns moving south from Ossetia into Georgia proper had according to eyewitnesses halted in the vicinity of the Georgian town Gori, outside the original Ossetian conflict zone and some 70 kilometres short of Tbilisi.

Georgian President Mikheil Saakashvili in a late Monday evening television statement warned of Russia's intention to occupy all of Georgia and accused the Kremlin of committing "ethnic cleansing" by invading Georgia via the Ossetia and Abkhazia provinces.

Rumours flew through the Georgian capital late Monday night and early Tuesday morning of a fast-moving Russian tank offensive intent on throwing out the Georgian national government.

But as Tuesday dawned the Georgian capital was quiet, having passed its first night in five days without a Russian airstrike in the vicinity. Traffic was moving normally, but banks across Georgia were closed.

Strong Russian armoured columns on the second western front held Georgia's Zugdidi district, adjacent to Abkhazia, by Tuesday morning, Georgia's Rustaveli-2 television reported.

The powerful force of some 9,000 naval infantry and 350 tanks and armoured personnel carriers had by that time not come into contact with the region's reported defenders: a brigade of US-trained Georgian infantry with combat experience in Iraq, and flown aboard US Air Force cargo jets into Tbilisi on Monday.

US President George W Bush on Monday condemned Russia's actions to date as a "dramatic and brutal escalation" apparently meant to oust the Georgian government.

"It now appears that an effort may be underway to depose (Georgia's) duly elected government," Bush said at the White House shortly after returning from the Olympics in Beijing. "I am deeply concerned by reports that Russian troops have moved beyond the zone of conflict."

Russian Prime Minister Vladimir Putin retorted sharply to the US president's words, calling US support for Georgia after the destruction of the Ossetian city Tskhinvali and the death of hundreds of its citizens under Georgian artillery fire "An example of truly startling cynicism."

Russian officials led by Putin have repeatedly cited NATO attacks on Serbia during the 1999 Kosovo war as justification for Russian attacks on Georgia during the present Ossetia war.

Russian President Dimitry Medvedev described Georgian military operations in South Ossetia as "genocide," Interfax reported.

"They were on a mass scale and were directed against individuals," he was quoted as saying.

The United Nations Security Council in New York held a fourth round of discussions late on Monday to discuss policy on resolving the conflict. The meeting, like the three before it, failed to develop a common position, with permanent members US and Russia disagreeing sharply.

Tbilisi was scheduled on Tuesday to see an unprecedented parade of foreign leaders led by French President Nicolas Sarkozy flying in to discuss possible ceasefire terms with Georgia's leadership.

Sarkozy was first planning to visit Moscow to discuss a three-phase ceasefire plan developed by the French government, and accepted by Saakashvili, with the Kremlin.

Other senior dignitaries scheduled to arrive in Georgia included the presidents of Lithuania, Poland, Ukraine, and Estonia, the Interfax news agency reported.

Russian military casualties since Thursday's outbreak of fighting was 16 dead and some 100 wounded, a Russian 58th Army spokesman said.

Georgian military casualties as of Monday were some 90 dead and 500 wounded, according to the latest Georgian Army estimates.

Confirmed civilian dead are in excess of 200, and may exceed 2,000, according to unconfirmed reports.

The UN High Commissioner for Refugees (UNHCR), Antonio Guterres, released 2 million dollars Monday to provide humanitarian support to people displaced by the fighting.

The UNHCR said the first flight carrying relief supplies was due to arrive Tuesday from Dubai with a second leaving Copenhagen on Wednesday. The two flights will carry enough relief supplies for at least 30,000 people reported to have fled South Ossetia.

About 25,000 refugees from South Ossetia's population of 70,000 have fled north and are living in camps and hostels in Valdikavkaz. Some 2,000 people, among them foreigners, fled Georgia into Armenia, (dpa)