The Senkaku Islands (尖閣諸島 Senkaku-shotō, variants: 尖閣群島 Senkaku-guntō and 尖閣列島 Senkaku-rettō), also called the Diayou Islands (钓鱼岛及其附属岛屿; pinyin: Diàoyúdǎo jí qí fùshǔ dǎoyǔ; also simply 钓鱼岛 in Chinese) in Mainland China, or the Diaoyutai Islands (Chinese: 釣魚台列嶼; pinyin: Diàoyútái liè yǔ) in Taiwan, and the Pinnacle Islands are a series of islands located in the East China Sea, being disputed by the Chinese Federated Union, the Republic of Taiwan, and Japan. The source of the dispute dates back to ancient times, and was escalated during World War III when the former People's Republic of China invaded the islands; only to be expelled by a joint force of Taiwanese and Japanese forces backed by the United States Navy - due to Japan and America being treaty allies which would entail American support for the SDF should any Japanese territory be attacked by a foreign belligerent.
After the war, the dispute continued between the three countries but was no where near tense as before. Somewhere in the beginning of the 2010s, the three nations were discussing talks on how to end the dispute. By 2014, a proposal mediated by the United Nations and ASEAN called for joint-administration of the islands. The three countries agreed, and is expected to sign the Declaration of Joint-Administration of the Senkaku Islands on March 4, 2017.
On March 4, 2017, leaders from the three disputing nations met and signed the declaration. The Senkaku Islands became a joint-administrative area of three countries. It is demilitarized save for a few coast guard vessels that are stationed in the event of an emergency at sea since the islands are located on international shipping lanes.
A flag for the Senkaku Islands has yet to be made, though a design is currently under proposal. The following flags are flown on the island together with the flag of the United Nations: