(LEAD) Yoon, Biden visit Air Force operations center

(ATTN: UPDATES throughout with visit; CHANGES headline, photo)
By Lee Haye-ah

SEOUL, May 22 (Yonhap) -- President Yoon Suk-yeol and U.S. President Joe Biden visited an Air Force operations center Sunday on the last stop of Biden's three-day trip to South Korea.

The two visited the Korean Air and Space Operations Center at Osan Air Base in Pyeongtaek, 70 kilometers south of Seoul, and met with American and South Korean troops stationed there.

The visit underscored the allies' firm readiness against North Korea's nuclear and missile threats after Yoon and Biden agreed during Saturday's summit to expand the scope of combined military exercises.

Biden was the first U.S. president to visit the center, which is situated in an underground bunker and serves as a key command post for air and space operations, while Yoon was the first South Korean president to do so in 13 years.

Before heading to the air base, Biden met with Hyundai Motor Group Chair Euisun Chung, who announced plans to invest an additional US$5 billion in the U.S. for robotics and autonomous driving software development.

On Saturday, the company announced plans to invest $5.54 billion in the construction of a dedicated electric vehicle and car battery manufacturing plant in Georgia, the United States.

Biden is set to head to Japan on Sunday afternoon.