(ATTN: UPDATES throughout with start of summit, Biden's visit to cemetery; CHANGES headline; ADDS photos)
By Lee Haye-ah
SEOUL, May 21 (Yonhap) -- President Yoon Suk-yeol and U.S. President Joe Biden held their first summit in Seoul on Saturday on a range of issues expected to include North Korea's nuclear program and supply chain risks.
Biden arrived at the new presidential office in Seoul's central district of Yongsan and was greeted by Yoon at the entrance before the two entered the building for a series of talks.
The summit will first be held in a small group, after which the two leaders will have a casual private meeting and then be joined by their aides for an expanded meeting.
The summit will end with a joint press conference inside the presidential office building where renovation work is still under way after Yoon relocated the presidential office from Cheong Wa Dae to what was formerly the defense ministry headquarters.
Before arriving for the talks, Biden visited Seoul National Cemetery to pay tribute to fallen soldiers.
Yoon and Biden are expected to discuss the full range of security and economic challenges facing the allies and the region, as both countries have claimed a North Korean nuclear or intercontinental ballistic missile test appears to be imminent.
South Korea's presidential office has said the first thing the two sides will do will be to come up with an "action plan" for how South Korea and the United States will strengthen "extended deterrence," a term that refers to the U.S. deployment of both conventional and nuclear assets to defend an ally.
In the event North Korea carries out a major weapons test during Biden's stay, the two leaders will immediately take command of the two countries' combined forces, according to the presidential office.
The summit is also expected to cover a range of economic issues as the U.S. seeks to bolster supply chains with key allies and friendly nations amid a global shortage of semiconductors and other key materials.
Yoon plans to announce South Korea's participation in the Indo-Pacific Economic Framework, an initiative that excludes China and was proposed by Biden to ensure secure and resilient supply chains and set the rules of the digital economy, among other things.
Biden arrived in South Korea the previous day on his first visit to the country as president and only 10 days after Yoon took office.
On the first stop of his three-day visit, Biden visited a Samsung semiconductor plant in Pyeongtaek, 70 kilometers south of Seoul, Friday, underscoring the two countries' commitment to working together to strengthen supply chains.
He was joined by Yoon and the two were given a personal tour of the sprawling compound by Samsung Electronics Vice Chairman Lee Jae-yong.
Yoon told Biden that the facility is "the site of the industrial and technology alliance between South Korea and the United States," a presidential official told reporters Saturday.
Yoon also said semiconductors are the core of the bilateral alliance and that advanced industries are only made possible by a free environment and creativity, and impossible without a liberal democratic system, according to the official.
Biden agreed with Yoon's remarks, the official said.
After the summit, Biden will attend a state dinner hosted by Yoon at the National Museum of Korea.
On Sunday, the two leaders will jointly visit the Korean Air and Space Operations Center, a key Air Force operations center at Osan Air Base in Pyeongtaek, where they will be briefed on its activities and encourage South Korean and U.S. service members.
Biden will depart for Japan on Sunday afternoon to continue on the second leg of his tour.
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