Former Japanese Ambassador to the United States Takakazu Kuriyama, who was involved in bilateral talks for the 1972 reversion of Okinawa Prefecture, died of pneumonia at a hospital in Tokyo on Wednesday, his family said Thursday. He was 83.

A native of Tokyo, Kuriyama left the University of Tokyo to enter the Foreign Ministry in 1954. He assumed key posts at the ministry, including director general of the North American Affairs Bureau and vice foreign minister, before becoming ambassador in 1992.

As a diplomat, Kuriyama was involved in negotiations for the United States to return Okinawa to Japan, 27 years after the U.S. took control of the prefecture at the end of World War II.

He also helped draft a joint statement on normalizing diplomatic relations with China in 1972.