Chang Ho-jin, new foreign policy adviser to President Yoon Suk Yeol, arrived in Washington, D.C., on Thursday to meet with officials and discuss the countries' alliance, the upcoming US election and other bilateral issues.

Chang's trip came days after he was replaced as South Korea's top national security adviser and assigned to the newly created position of Yoon's special adviser for foreign and security affairs in a surprise reshuffle.

"It has been nearly a year since we had the Camp David summit," Chang told reporters upon arriving at Dulles International Airport, referring to the landmark trilateral leaders' gathering among South Korea, the United States and Japan.

"I plan to discuss how we can effectively conclude issues, like the South Korea-US alliance, during the remaining term of the Biden administration," Chang said.

"Since my position has changed, I plan to talk about my duties as well and hear about how the presidential election in the US has been unfolding," he added.

The new unification strategy, announced by Yoon in his Liberation Day speech Thursday, will also be among the agenda items for discussions with people he will meet, Chang said.

Chang said he had "nothing special to say" about the latest reshuffle.

The unexpected replacement of Chang and the defense minister has spawned various speculation about the real reasons behind the reshuffle, including Yoon's close ties with the new defense minister, Kim Yong-hyun.

Shin Won-sik, the outgoing defense minister, succeeded Chang as Yoon's top security aide. Shin will continue to serve as defense minister until his successor takes office after a parliamentary confirmation hearing.

Chang, a career diplomat and former vice foreign minister, was appointed as the national security adviser in January. (Yonhap)