Japanese Prime Minister Yoshihide Suga and U.S. President-elect Joe Biden held their first phone conversation early Thursday.

According to Japan's Kyodo News and NHK, Suga congratulated Biden on his election win and emphasized the need to further enhance their alliance as it is indispensable in achieving peace and prosperity in the Asia-Pacific and around the world.

Suga called for the allies to unite in achieving a "free and open Indo-Pacific," a U.S. strategy aimed at countering Chinese Communist Party aggression, and sought Washington's support in repatriating Japanese abductees in North Korea.

Biden reconfirmed the U.S. commitment to defend Japanese territory from an external attack, specifically referring to Article 5 of the U.S.-Japan Treaty of Mutual Cooperation and Security, which covers the disputed Senkaku or Diaoyu Islands.

While Japan administers the islands in the East China Sea, China also claims ownership.

Kyodo News said Suga and Biden agreed to arrange Suga's visit to Washington for a leaders' summit, adding that it will likely come soon after Biden's January 20 inauguration.