President Ma Ying-jeou is visiting a small island in the East China Sea to reassert Taiwan's sovereignty and its role in the contested region, one of the key issues of his administration that ends next month.

Ma's visit on Saturday to Pengjia, roughly 35 miles (56 kilometers) north of Taiwan proper, comes four years after he last visited the island to propose a plan to address territorial disputes between China, Taiwan and Japan over the nearby chain known as Senkaku in Japanese and Diaoyutai in Chinese.

During his eight-year term, Ma has sought to position Taiwan as a mediator in the region's numerous territorial disputes while asserting its own claims.

Ma flew to Taiping Island in the South China Sea in January, which Washington, a crucial ally, called "extremely unhelpful."