Yang Fu-cheng speaks at a press conference in Tokyo after his case was dismissed on Jan. 11, 2022. (Kyodo)

A Tokyo court dismissed Tuesday a lawsuit filed by three Taiwanese men born in Taiwan during Japan's colonial rule seeking to have their Japanese nationality reinstated after they automatically lost it following World War II.

According to the suit filed with the Tokyo District Court, all three plaintiffs, including Yang Fu-cheng, 99, are in their 80s or 90s and were born to parents of Taiwanese origin.

Japan renounced its territorial rights over its overseas colonies, including Taiwan, when the San Francisco Peace Treaty took effect in 1952, ending the legal state of war. Japanese nationals of Taiwanese descent were considered at that time to have abandoned their citizenship.

In 1962, the Supreme Court ruled that Japanese nationals of Taiwanese descent lost their citizenship when a peace treaty signed by Japan and Taiwan entered into force in 1952. The island was under Japanese colonial rule between 1895 and 1945.

The plaintiffs argued that based on the Universal Declaration of Human Rights, which states that "no one shall be arbitrarily deprived of his nationality," an individual should not be able to lose their citizenship against their will.

But the court rejected the claim, saying the document by the United Nations is not legally binding and that there is "no international law that requires the consent of an individual when his nationality changes due to a change in territorial rule."

At a press conference in Tokyo after the ruling, Yang said he was "very disappointed" and indicated he intends to file an appeal.