WASHINGTON (CNN) -- Russia pressed the United States on Wednesday to choose between "a real partnership" with Moscow or an "illusory" relationship with U.S. ally Georgia.

Washington said it's sticking with Georgia.

"As to choosing, the United States has made very clear that it is standing by the democratically elected government of Georgia," Secretary of State Condoleezza Rice said Wednesday.

She spelled out the Bush administration's stance after Russian Foreign Minister Sergei Lavrov called Georgia's government "a special project for the United States."

"And we are aware that the U.S. is uptight about this project," Lavrov said in remarks broadcast on Russian television. "But a choice will have to be made someday between considerations of prestige related to an illusory project and a real partnership in matters which indeed require collective efforts."

Rice, amid reports that Russian troops remained on the move Wednesday, pushed Russia to abide by a cease-fire signed Tuesday by the Russian and Georgian presidents.

Russian military action in Georgia "must stop and must stop now," Rice said.

Rice said Moscow already faced "quite significant" diplomatic consequences over its conflict with Georgia before Tuesday's cease-fire agreement, which calls for Russian and Georgian troops to return to pre-conflict positions.

Bush said reports he had received were contrary to Russian assurances that it had halted military operations. Bush said he was told the Russian military had blocked Georgia's major east-west highway, and had soldiers at the main port at Poti. There were reports that some ships had been attacked, he said.

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Russia has likely moved additional troops into the disputed Georgian provinces and into Georgia proper over the past several days, several administration officials told CNN on Wednesday.

The officials said the United States now believes Russia may have 15,000 or more troops in the region. That would be an increase from the 8,000-10,000 the U.S. government estimated when the fighting began. A Bush administration official stressed that the scope of Russia's military effort remains unclear.

Any violations of the cease-fire would call into question Russia's "suitability" as an international partner, Rice told reporters before leaving on a diplomatic trip to Europe.

Bush administration officials told CNN the United States and its European allies were considering kicking Russia out of the G-8, the group of the world's largest industrial economies, and other international organizations as punishment for its actions in Georgia.

Rice discounted concerns that Moscow would no longer assist Washington on thorny diplomatic issues such as efforts to halt nuclear programs in Iran and North Korea, saying it had its own interests at stake.

"Let's be very clear whose interests are being served by the partnership that Russia and the United States have engaged in on Iran or North Korea," she said. "Again, it's not a favor to the United States."

Russia sent troops and tanks into the breakaway Georgia region of South Ossetia last week after Georgia's military acted to clamp down on Russian-linked separatists there. Separatists in South Ossetia want independence -- or unification with North Ossetia, which is in Russia.

The conflict quickly spread to other parts of Georgia, including Abkhazia, another separatist region.

Georgia has been a close U.S. ally, contributing troops to the war in Iraq and seeking to join NATO with Washington's support. In a CNN interview Wednesday, Georgian President Mikheil Saakashvili criticized the United States for not doing more to help his nation. Watch Saakashvili fault the U.S. response »

"America is losing the whole region, and this is the region of eastern and central Europe," said Saakashvili, who called for the United States and European powers to send peacekeepers to the region. "This is much bigger than any other place where there is American influence, and this is the most natural allies of America."

But later Wednesday, in an interview with CNN's "Situation Room," Saakashvili seemed to have a change of heart. He said that after speaking with President Bush earlier in the day, he felt "there will be no compromise at the expense of our territorial integrity."

"I never accused the United States in the first place of anything," he said. "I just said that the Russians mistook some of the statements at certain levels."

Rice defended the administration's response to the fighting. Watch Bush express support for Georgia's democracy »

"I don't think you can have any doubt but that the United States has, from the very beginning, believed that the South Ossetian situation needed to be resolved and resolved peacefully, as we've been working for months and months and months to do, but that Russia seriously overreached, that Russia engaged in activities that could not possibly be associated simply with the crisis in South Ossetia," she said.

U.S. officials said they warned Saakashvili not to provoke Russia militarily by sending Georgian troops into South Ossetia and they had ruled out any U.S. military action to defend Georgia.

Rice spoke after Bush's announcement that U.S. aircraft and ships would deliver humanitarian aid to victims of the fighting.

Bush and Rice warned Russia not to interfere with the delivery of humanitarian aid, noting that Tuesday's French-brokered cease-fire allows for the delivery of international relief, and expressed concern over reports that Russian units were continuing to advance into Georgian cities despite Tuesday's cease-fire. Watch Russian tanks move toward Tbilisi »

"We expect Russia to meet its commitment to cease all military activities in Georgia, and we expect all Russian forces that entered Georgia in recent days to withdraw from that country," Bush said.

Rice will travel to France and then head to Tbilisi, Bush said.

Next week, Rice will travel to NATO headquarters in Brussels, Belgium.

Russia's move into Georgia came amid a struggle between the United States and Russia for influence within Eastern Europe. From Russia's point of view, American support for Georgia is a direct threat to its influence.

By striking heavily in Georgia, Moscow is sending a signal to other former Soviet republics, such as Ukraine and Moldova, said Sarah Mendelson, the director of the Human Rights and Security Initiative at the Center for Strategic and International Studies in Washington.

"If I were a neighbor of Russia and I saw what Russia had done in Georgia, I would be very nervous," Mendelson said. "I think those countries that are leaning toward the West are very nervous today."

CNN's Zain Verjee contributed to this report.

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