SOCHI (Russia)  - German Chancellor Angela Merkel and Russian President Dmitry Medvedev clashed on Friday over the status of Georgia's rebel regions, which Medvedev said Tbilisi was unlikely to regain. "Unfortunately after what has happened it is unlikely Ossetians and Abkhaz can live in one state with Georgians," Medvedev said at a tense news conference with Merkel after talks on the conflict over the rebel region of South Ossetia. "Russia, as a guarantor of security in the Caucasus and the region, will make a decision that unambiguously supports the will of these two Caucasus peoples," Medvedev said, referring to the provinces of Abkhazia and South Ossetia. The Russian leader was unapologetic in the face of Western criticism of Moscow's military action in Georgia, saying Moscow would not hesitate to act similarly again to protect its citizens. Medvedev added that while Russia was not opposed to bringing in other international peacekeepers, in practice such peacekeepers were distrusted by the separatist regions themselves. However, Merkel expressed diametrically opposite views on Georgia's future at the news conference at the Russian leader's Black Sea coastal residence, saying that keeping the separatist zones within Georgia was a "starting point" for any peace agreement. She also said maintaining the territorial integrity of Georgia must be a "basic point" in any plan for restoring peace in the Caucasus. She said Russia's military response to a Georgian attack on South Ossetia had been "disproportionate" and insisted "there is an elected government in Georgia with which we have to discuss and negotiate." Merkel added that Georgia's ambitions to join Nato remained "valid. Meanwhile, US President George W Bush sternly warned Russia against "bullying and intimidation" of its neighbours and vowed Washington would not back down in its support for embattled ally Georgia. Bush called on Russia to fulfil its pledge to withdraw troops from Georgia and to pursue cooperation with neighbouring states instead of what he called a Cold War-era approach of confrontation. "Only Russia can decide whether it will now put itself back on the path of responsible nations or continue to pursue a policy that promises only confrontation and isolation," a solemn Bush said outside the Oval Office. Bush said the United States would stand behind Georgia and called on Moscow to embrace the spread of democracy in the region. "The Cold War is over. The days of satellite states and spheres of influence are behind us." The US President said a "contentious relationship" between Russia and the United States was in neither nation's interests. But the Russian President also said on Friday after talks with German Chancellor Angela Merkel that Russia wants to avoid any damage to relations with the West over its conflict with Georgia. Bush praised Georgia as a "courageous democracy" and noted that it had deployed troops to Afghanistan and Iraq.