There were few signs Russia was following the terms of a cease-fire to end the short war, which has driven tensions between Russia and the West to some of their highest levels since the breakup of the Soviet Union.
In Paris, the French foreign minister said it appeared "we are witnessing the start" of a Russian withdrawal, but warned France would call an emergency meeting of the European Council to talk about consequences for Russia if that was not the case.
But U.S. defense and military officials said they had seen no significant movement yet of Russian troops withdrawing from Georgia.
Secretary of State Condoleezza Rice, on her way to an emergency meeting of NATO foreign ministers, said Russia was playing a "very dangerous game and perhaps one the Russians want to reconsider."
She said the United States and its allies would not allow Russia to draw a "new line" through Europe and intimidate former Soviet republics and former satellite states.
The foreign ministers were set to meet Tuesday in Brussels, Belgium, to consider whether to go ahead with upcoming activities planned with Russia, from military exercises to diplomatic meetings.
The European Union-brokered peace plan signed by both Russian President Dmitry Medvedev and Georgian President Mikhail Saakashvili calls for both sides to pull forces back to the positions they held before fighting broke out Aug. 7. Medvedev had told French President Nicolas Sarkozy on Sunday that Russian troops would begin pulling back on Monday, but stopped short of promising they would return to Russia.
Russia sent its tanks and troops into Georgia after Georgia cracked down on the separatist, pro-Russian province of South Ossetia. Fighting has also flared in a second breakaway region, Abkhazia.
In Moscow, the deputy chief of the Russian general staff, Col.-Gen. Anatoly Nogovitsyn, told a briefing that "today, according to the peace plan, the withdrawal of Russian peacekeepers and reinforcements has begun" and said forces were leaving Gori.
But Russian tanks and troops roamed freely around the city and made forays toward the Georgian capital of Tbilisi, 55 miles to the southeast. Russia also kept control of the critical highway that slices through Georgia's midsection.
AP reporters saw four Russian armored personnel carriers, each carrying about 15 men, rolling from Gori to Igoeti, a crossroads town even closer to Tbilisi, passing Georgian soldiers who sat by the roadside.
The Russians moved into Igoeti then turned off onto a side road. As the Russian vehicles rolled past a group of Georgian soldiers and policemen, one swerved and scraped a new Georgian police car. The Georgians looked down at their fingernails.
U.S. officials, speaking on condition of anonymity because they were discussing intelligence reports, said at least one Russian battalion equipped with more than a dozen SS-21 missile launchers had moved into South Ossetia, within range of Tbilisi. Nogovitsyn disputed the claim.
The RIA-Novosti news agency reported that the leader of South Ossetia, Eduard Kokoity, asked Russia on Monday to establish a permanent base there.
Nogovitsyn said the Russian troops were pulling back to South Ossetia, but the boundaries of the Russian presence remained unclear. He said "troops should not be in the territory of Georgia," but it was unclear whether that excluded patrols.
Russian troops were restricting access to Gori, where shops were shut and people milled around on the central square.
"The city is a cold place now. People are fearful," said Nona Khizanishvili, 44, who fled Gori a week ago for an outlying village and returned Monday, trying to reach her son in Tbilisi.
Georgia's Rustavi-2 television showed footage of a Russian armored vehicle smashing through a group of Georgian police cars barricading the road to Gori on Monday. One of the cars was dragged along the street by the Russian armor. Georgian police stood by without even raising their guns as the Russian vehicle crushed through the roadblock.
In Senaki, a series of explosions were heard from the military base in the afternoon. Later, three separate blasts that appeared to destroy the airport runway shook the leaves on trees more than a mile away.
Georgian Interior Ministry spokesman Shota Utiashvili said Russian forces had blown up the runway. There was no confirmation from Russian military officials.
Earlier, Russian troops had allowed displaced people to get to the base to retrieve their belongings. Cars emerged loaded with goods, including televisions and refrigerators.
A planned exchange of prisoners captured during the fighting fell through, with each sides blaming the other. It was not clear how many prisoners were to be exchanged. Georgian officials another attempt could take place Tuesday.
In Vladikavkaz, near the border with Georgia, Medvedev gave medals to 30 soldiers and servicemen involved in the conflict. He called them heroes and said they had fought "a cowardly aggression.
"I am sure that such a well conducted, effective peacemaking operation aimed at protecting our citizens and other people will be among the most glorious deeds of the Russian military," Medvedev said.
While Western leaders have called Russia's response disproportionate, Medvedev repeated Russian accusations of genocide.
"The world realized that even now there are political freaks who were ready to kill innocent people for the sake of political fashions and who compensated for their own stupidity by eliminating a whole nation," he said.
An Associated Press cameraman was slightly injured outside Gori after four men in camouflage, possibly from an Ossetian militia, pulled up in a car and told him to stop filming.
When the cameraman resisted, the driver produced a pistol and started shooting at the ground. The cameraman, who sustained light ricochet wounds to his legs, handed over the cassette.
The Pentagon said that up to five C-130 aircraft are expected to fly into Georgia Tuesday with supplies, and that three had landed Monday as part of the relief effort. In addition to food, medical aid, tents and bedding, the U.S. is sending forklifts to help unload and move the supplies.
The United Nations refugee agency said more than 158,000 people had been displaced by the conflict, most of them within Georgia.
"I think the Russians will pull out, but will damage Georgia strongly," said Givi Sikharulidze, who lives in Tbilisi. "Georgia will survive, but Russia has lost its credibility in the eyes of the world."
Associated Press writers David Nowak, Jim Heintz, Steve Gutterman and Jill Lawless in Moscow, Matti Friedman in Gori, Georgia; Christopher Torchia and Misha Dzhindzhikhashvili in Tbilisi, Georgia; Bela Szandelszky in Senaki, Georgia; Mansur Mirovalev in Vladikavkaz, Russia; and Lolita C. Baldor and Pauline Jelinek in Washington contributed to this report.