President Moon Jae-in left the United States on Saturday following a four-day trip for summit talks with U.S. President Joe Biden.

Moon boarded his Air Force One in Atlanta to head back home from his first overseas trip since the outbreak of the COVID-19 pandemic.

Moon and Biden held summit talks for almost three hours on Friday at the White House and adopted a joint statement vowing cooperation on the North Korean nuclear issue, COVID-19 vaccines and new industries.

The two leaders agreed to establish a global vaccine partnership in the summit, with President Biden pledging to provide vaccines for 550-thousand South Korean troops.

On Saturday, Samsung Biologics, a South Korean biopharmaceutical firm, signed an agreement to manufacture the U.S. drugmaker Moderna's COVID-19 vaccine at its local factory.

The deal was signed during a South Korea-U.S. vaccine partnership event in Washington, with President Moon in attendance.

Before departing the United States, the president made a brief visit to a Georgia plant construction site of SK Innovation, a South Korea-based battery maker.

He is set to arrive at Seoul Air Base in Seongnam on Sunday evening Korea time.