In a simultaneous two-chamber vote at the United Nations, Japanese international law professor Yuji Iwasawa was elected to serve as a judge on the International Court of Justice.

Iwasawa, 64, fills a vacancy left by 85-year-old Hisashi Owada, who retired on June 7. He will serve the remainder of Owada's nine-year term, which runs until Feb. 5, 2021.

"I want to dedicate myself to the promotion of rule of law, making use of my past experience," Iwasawa told reporters Friday after his unopposed candidacy won support from 184 members of the 193-strong General Assembly and all 15 Security Council members.

Iwasawa, a professor of international law at the University of Tokyo's graduate school, is the fourth Japanese to serve at the world court, which sits at The Hague.

Among other high-level international roles, he has chaired the U.N.'s Human Rights Committee and served as a judge for the Asian Development Bank's administrative tribunal.

Owada, father of Crown Princess Masako, is a former diplomat who was vice foreign minister and ambassador to the United Nations. During his 15-year stint at the ICJ, he served as chief of the world court between 2009 and 2012, becoming the first Japanese to do so.

The ICJ is composed of 15 judges elected to nine-year terms, with no two judges of the same nationality allowed to serve at the same time. The court is the principal judicial organ of the United Nations, functioning to settle disputes between member states and present advisory opinions that carry weight.