Biden lands in South Korea on Friday evening, where he meets new President Yoon Suk-yeol, a relative newcomer to politics, for the first time in person. The two will tour a Samsung Electronics plant together on Friday before a full day of events on Saturday.
"I think (Biden's visit) will serve as an opportunity for the Korea-US alliance to become stronger and more inclusive because there are many changes happening in the international community," Yoon told reporters outside his office on Friday.
Biden and Yoon may quickly move from formalities to dealing with a weighty issue with North Korea at the top of the agenda. Leader Kim Jong-un abandoned a freeze on intercontinental ballistic missile testing and appears poised to resume testing of nuclear bombs, perhaps while Biden is in the region.
US co-operation with South Korea and Japan "will only strengthen in the face of further provocations" by North Korea, Biden national security adviser Jake Sullivan told reporters on the way to South Korea when asked about the possibility of a weapons test.
The United States has told allies and China that such a provocation during the US visit would "cause adjustments to the way that our military is postured in the region", he said.
Yoon has signalled he would take a tougher line on North Korea than his predecessor and is expected to ask for Biden's help. Yoon has warned of a pre-emptive strike if there is a sign of an imminent attack and vowed to strengthen the South's deterrent capability.
North Korea has revealed a COVID-19 outbreak in the past week, but it has ignored calls to return to diplomacy.
Washington has said it is open to direct talks with Kim, but it has not publicly offered new ideas about how to coax the country's leadership into conversation. Biden decided not to visit the heavily fortified demilitarised zone separating the South from North Korea.
Countering China's presence in the region is a key Biden theme on the trip, but South Korea is likely to offer a cautious public tone on the topic given Beijing is Seoul's top trading partner.
