There are two governments that claim to represent China - the People's Republic of China (PRC) based on the mainland and the Republic of China (ROC) based in Taiwan. Both accept the One China principle that Taiwan is part of China, but they disagree on which government is legitimate. Most countries follow the One China policy of only recognizing one or the other to maintain diplomatic relations. While the US initially supported the ROC, it switched recognition to the PRC in 1972. Hong Kong and Macau are special administrative regions of China with a high degree of autonomy under the One Country, Two Systems framework.