U.S. President Joe Biden and his new South Korean counterpart will search for ways on Saturday to break a diplomatic stalemate with North Korea, as they worry Kim Jong Un could lash out with new nuclear tests.

Biden and Yoon Suk-yeol will meet in Seoul for their first diplomatic engagement since the South Korean president's inauguration 11 days ago. The friendly encounter between allies is clouded by intelligence showing North Korean leader Kim is prepared to launch nuclear or missile tests.

A senior Biden administration official told reporters on Saturday that the two leaders will discuss nuclear cooperation and that Washington remains ready for diplomacy with North Korea.

"It is very much our desire that we find ways to have a diplomatic approach," the official said. "We have made very clear we're prepared to talk to them, and with no preconditions, and we're also prepared to take steps to address their domestic challenges, including COVID."

But it was unclear how Biden and Yoon would jumpstart talks with the North Koreans, who have rebuffed Washington's efforts at engagement since Biden took office last year.

Yoon has signalled a tougher line on North Korea than his predecessor and is expected to ask for Biden's help. Yoon has warned of a preemptive strike if there is a sign of an imminent attack and vowed to strengthen the South's deterrent capability.

North Korea's first acknowledged COVID-19 outbreak, which the U.S. official described as "quite serious", may provide an opening.

"We are very concerned about the COVID situation," the official said. "We are very sensitive to the fact that they appear to be facing a quite serious situation, and I think you've seen we stand ready to work with others in the international community as needed to provide assistance."

North Korea reported more than 200,000 new patients suffering from fever for a fifth consecutive day on Saturday, but the country has little in the way of vaccines or modern treatment for the pandemic.

That has raised the prospect of a diplomatic opening as well as a humanitarian crisis or the prospect of deadlier new COVID variants, health officials have said.

Washington has said it has no plans to send vaccines directly to the country, but Yoon may push Biden to do so. North Korea has not accepted offers of COVID help from South Korea, the United States and international vaccine sharing agencies.


A North Korean weapons test could overshadow Biden's broader trip focus on China, trade and other regional issues.

Biden is set to introduce an Indo-Pacific economic framework that excludes China, which he has called an autocracy, and has called for more cooperation with countries that "share our values", like South Korea.

Although White House officials have sought to play down any explicit message of countering China, it is a theme of Biden's trip and one that has caught the eye of Beijing.

"Jake Sullivan said that Biden's trip to Asia is not aimed at confronting China," Chinese envoy for Korean affairs Liu Xiaoming, said on Twitter, referring to Biden's national security adviser.

"We hope that the U.S. will match its words with deeds and work with countries in the region to promote solidarity and cooperation in the Asia-Pacific, instead of plotting division and confrontation."

Liu called on the United States to join efforts to foster an "open & inclusive circle of friends" in the region, instead of putting together a "closed & exclusive clique".

"It should do more to contribute to peace & development in the Asia-Pacific, instead of creating turbulence & chaos in the region," he said.

Yoon, keen for South Korea to play a bigger role in regional issues, is expected to be among the inaugural members of Biden's Indo-Pacific Economic Framework (IPEF), which will be announced during the trip to set standards on labour, the environment and supply chains.

But given that Beijing is Seoul's top trading partner, he is likely to strike a cautious tone in public on the topic of explicitly countering China, saying on Friday that joining the framework does not have to conflict with the countries' economic ties.

Biden also plans to use the visit to tout investments in the United States by Korean companies, including a move by South Korea's Hyundai Motor Group to invest about $5.54 billion to build its first dedicated full electric vehicle and battery manufacturing facilities in the United States.