President Yoon may not have had time to meet with Nancy Pelosi, but he did have time to meet with Bill Gates to discuss vaccine development:

President Yoon Suk-yeol met with Microsoft co-founder Bill Gates on Tuesday and discussed cooperation on vaccine development and other health issues.
During the meeting at the presidential office, Yoon praised Gates for his contributions to modern industrial technology and infrastructure and for his efforts to increase access to vaccines and treatments in developing countries.
He also thanked Gates, who co-chairs the Bill & Melinda Gates Foundation, for helping South Korea’s SK Bioscience Co. develop the country’s first homegrown COVID-19 vaccine in June.
“On behalf of the government of the Republic of Korea, I too would like to establish substantive cooperative relations with your foundation so that our country can contribute to promoting the health of the world’s citizens while continuing to build advanced bio health technologies,” he said.
Yonhap
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