Prime Minister Shinzo Abe and Adm. Harry Harris, head of the U.S. Pacific Command, agreed Tuesday to steadily implement revised cooperation guidelines to strengthen the Japan-U.S. defense alliance and secure peace and stability in Asia.

At their meeting in Tokyo, Abe and Harris agreed on the importance of working together with South Korea in dealing with North Korea’s ballistic missile development efforts, according to the Foreign Ministry.

Abe told Harris that the security legislation and revisions to the bilateral guidelines last year have helped Japan and the United States to work more closely in responding to North Korea’s repeated ballistic missile launches, a development he called “encouraging.”

The controversial legislation expanded the role of the Self-Defense Forces, allowing them to come to the aid of allies under attack and engage in collective self-defense. Successive governments prior to Abe’s had interpreted the war-renouncing Constitution to mean that Japan possessed the right to collective self-defense but could not exercise it.

“I believe, and I know Adm. Kuwano believes, that the Japan-U.S. alliance is the key to peace and stability in (the Asian region),” Harris told Abe, referring to Katsutoshi Kawano, chief of the SDF’s Joint Staff, with whom he held talks on Monday and Tuesday.

Tokyo has raised concerns over Chinese naval vessels sailing into and near Japanese territorial waters in the East China Sea, including waters around the uninhabited Senkaku Islands. Beijing claims ownership of the islets.

Harris’ visit comes after an international tribunal found no legal basis for China’s claims to historic and economic rights over most of the South China Sea, ruling on a case brought by the Philippines.

According to the ministry, Abe and Harris also discussed the planned relocation of the U.S. Marine Corps Air Station Futenma in Okinawa from a densely populated area to a more sparsely populated coastal location elsewhere in the island prefecture.

The plan has sparked intense local criticism and a legal battle between the central government and the prefecture, which wants the base to be relocated outside of Okinawa.

Abe told Harris the Japanese government’s position remains unchanged that the base’s relocation to the Henoko coastal site is the only solution to issues concerning Futenma.

Harris responded with thanks for the Japanese government’s assistance with U.S. military activities in Okinawa, including on the issue of the Futenma relocation, according to the ministry.