Former U.S. Ambassador to Japan Caroline Kennedy said Monday that Okinawa is the linchpin to the U.S.-Japan security alliance.

She made the remarks as she sought understanding from 20 visiting high school and university students from Okinawa on the importance of the U.S. military presence in the prefecture.

During their meeting in New York, the beginning of which was open to the press, Kennedy, the 60-year-old daughter of the late U.S. President John F. Kennedy, said the U.S.-Japan alliance is one of the most important alliances in the world.

She also said her service as U.S. ambassador to Japan from November 2013 to January 2017 was one of the highest honors in her life, and expressed willingness to further advance the bilateral relationship.

Okinawa hosts the bulk of U.S. military facilities in Japan. The U.S. presence there has long been a source of tension between the prefectural and central governments.

Accidents involving American military aircraft and crimes involving U.S. personnel have angered local residents.

The students are visiting the United States on a program organized by the Japanese Foreign Ministry, which plans to continue sending students from Okinawa approximately once a year in the future.