Political status of Taiwan across the Taiwan strait is only temporary and a reunified China including both mainland China and Taiwan will be the result. The position of the Republic of China had been that it was a "de jure" sovereign state. "Republic of China," according to the ROC government's definition, extended to both mainland China (Including Hong Kong and Macau) and the island of Taiwan. In 1991, President Lee Teng-hui unofficially claimed that the government would no longer challenge the rule of the Communists in mainland China, the ROC government under Kuomintang (KMT) rule actively maintained that it was the sole legitimate government
Mainland China in English, is commonly applied by SAR governments to represent non-SAR areas of PRC, including Hainan province and coastal regions of mainland China, such as "Constitutional and Mainland Affairs" () and Immigration Departments. In the Mainland and Hong Kong Closer Economic Partnership Arrangement (as well as the Mainland and Macau Closer Economic Partnership Arrangement) the CPG also uses the Chinese characters "inner land", with the note that they refer to the "customs territory of China". In the United States' Taiwan Relations Act, the ROC-controlled islands of Quemoy and Matsu were excluded from the definition of "Taiwan". The House Foreign Affairs