The United States said on Friday that Georgia\'s three restive regions and Russian intimidation in the ex-Soviet Caucasus meant Georgia faced a real threat of instability after last month\'s bloodless revolution. U.S. Defence Secretary Donald Rumsfeld was meeting Georgia\'s new leaders, including Acting President Nino Burdzhanadze, in Tbilisi to stress Washington\'s commitment to stability in the state, a U.S. official said. But the armed kidnapping on Friday of a co-founder of Georgia\'s main commercial bank underlined the problems that emerged when President Eduard Shevardnadze was forced to step down by protests over a disputed November 2 parliamentary poll. Burdzhanadze called on Georgians to remain calm after the capital was rattled by a series of violent incidents, including an explosion in front of state television headquarters and shots fired at the flat of a leading pro-Shevardnadze politician. Georgian developments are under close scrutiny by the West, keen to see completion of a $2.5 billion pipeline due to take Caspian oil to the Mediterranean as an alternative to the Gulf. \"The potential for instability is there and real,\" the U.S. official said, naming three Georgian regions as \"a very destabilising piece\" of the equation. He also said there was American concern over \"Russian intimidation\" of countries in the region, citing Moscow\'s failure to pull its troops out of Georgia as an example. As well as meeting Burdzhanadze, Rumsfeld was due to see Mikhail Saakashvili – the leader of the opposition protests that brought down Shevardnadze – State Minister Zurab Zhvanya and Foreign Minister Tedo Japaridze. Earlier this week, Washington issued a thinly veiled warning to Russia not to back breakaway Georgian regions. Tbilisi also accused Moscow of meddling when Russian officials met leaders of three Georgian regions – Abkhazia, South Ossetia and Adzhara. (Reuters)