The Treaty of Peace with Japan, signed in San Francisco on 8 September 1951, states in its Article 2, “Japan renounces all right, title and claim to the Spratly Islands and to the Paracel Islands”, which Japanese forces occupied just before and during World War II and from which they launched attacks on other countries in the region. However, the treaty does not say which nation is to have such right, title or claim to those islands, although the Vietnamese have asserted that, since those islands belong to Vietnam, it can be assumed that they reverted to Vietnam after Japan was divested of them. The Chinese have made a similar claim on behalf of Chinese ownership.

The Philippines and Vietnam were among the forty-nine states that signed the treaty. Neither the People's Republic of China, which had taken control of the Chinese mainland almost two years earlier, nor the “Republic of China”, which had fled to Taiwan but claimed to be the government of all of China, was invited to the San Francisco conference that produced the treaty. This was mainly because some of the participants in the conference recognized the People's Republic as the rightful government of China, while others continued to give recognition to the authorities on Taiwan as the government of all of China.

On 28 April 1952, the same day that the San Francisco Treaty entered into force, Japan and the “Republic of China”, which Japan then considered as the Chinese government, signed a separate Treaty of Peace in Taipei. In it, the two parties “recognized” that, under the San Francisco Treaty, Japan had “renounced all right, title, and claim to Taiwan (Formosa) and Penghu (the Pescadores) as well as the Spratley Islands and the Paracel Islands”, again without specifying which nation would have such right, title or claim. On 29 September 1972, Japan shifted its diplomatic relations from Taipei to Beijing by means of the Joint Communique issued during Prime Minister Kakuei Tanaka's visit to China.