Prime Minister Yoshihide Suga on Sunday congratulated Democrat Joe Biden on his election as the next U.S. president, expressing a desire to bolster bilateral ties.

"I look forward to working with you to further strengthen the Japan-U.S. Alliance and ensure peace, freedom, and prosperity in the Indo-Pacific region and beyond," Suga said in a Twitter post.

Under a postwar security treaty, Japan hosts around 55,000 American troops in exchange for help in defending against potential threats, including missile attacks from North Korea.