Sung Kim is scheduled to take up the post as U.S. ambassador to South Korea next week, a diplomatic source here said Thursday after his swearing-in ceremony.

Wendy Sherman, under secretary of state for political affairs, officiated at the ceremony at the State Department in lieu of Secretary of State Hillary Clinton, who canceled all scheduled activities throughout the day due to the death of her mother earlier this week, added the source.

"The new ambassador, Sung Kim, is expected to go to Seoul around Nov. 10 and he will immediately present credentials (to President Lee Myung-bak) to begin his work," the source said, requesting anonymity since the State Department has yet to announce a related schedule.

Kim, a career diplomat with expertise on the North Korean nuclear issue, will become the first Korean-born U.S. ambassador to Korea since the two sides forged diplomatic relations 129 years ago.

He had a confirmation hearing on July 21, and was confirmed by the Senate Committee on Foreign Relations a week later.

But Jon Kyl (R-AZ), assistant minority leader in the Senate, and some other senators had been reportedly blocking the confirmation process, apparently due to his displeasure with the Obama administration's policy on North Korea and other foreign affairs.

Kyl and the senators lifted their hold on the process while the South Korean leader was on a state visit to the U.S. in the middle of October.

Kim replaces Kathleen Stephens as Washington's top envoy in Seoul after her three-year stint. (Yonhap News)