Seoul, Oct 19 : The United States will likely replace its acting Ambassador to South Korea ahead of President Donald Trump's visit to the country later this month, diplomatic sources said on Sunday.

According to the sources, Acting US Ambassador Joseph Yun is expected to step down from his post around next Sunday, nine months after assuming the role earlier this year, Yonhap News Agency reported.

US Deputy Assistant Secretary of State Kevin Kim has been mentioned as Yun's potential replacement.

Trump is expected to visit South Korea from October 29-30 for the Asia-Pacific Economic Cooperation meetings scheduled to take place in the country, South Korea's National Security Adviser said earlier.

Yun took the post of acting Ambassador in January under the Joe Biden administration, just before Trump took office that month.

On Friday, the top military officers of South Korea and the United States held phone talks and discussed ways to strengthen cooperation for their alliance, the South's Joint Chiefs of Staff (JCS) said.

JCS Chairman General Jin Yong-sung and his US counterpart, General Dan Caine, noted the security situation on the Korean Peninsula remains stable on the back of their ironclad alliance and concurred on the importance of deterring North Korean threats through the South Korea-US combined defence posture, the JCS said.

The military chiefs agreed to discuss further alliance issues and ways to strengthen cooperation during their bilateral Military Committee Meeting scheduled to take place in Seoul next month.

Their phone call marked the first such conversation since Jin took office as JCS chairman late last month.

On Thursday, a top policy aide to South Korean President Lee Jae Myung said that Seoul and Washington are engaging in trade negotiations in the "most earnest and constructive" atmosphere to date, as they hash out details of Korea's $350 billion investment commitment under a trade deal struck in July.

Kim Yong-beom, the presidential chief of staff for policy, made the remarks upon arrival at an airport near Washington, amid growing speculation that South Korea and the United States have inched closer to an agreement to finalise the specifics of the trade deal.

Kim, along with Industry Minister Kim Jung-kwan, arrived in the US as Seoul steps up efforts to expedite negotiations with the US by sending top officials, including Finance Minister Koo Yun-cheol, to Washington this week.

"Taking stock of how (the negotiations) have so far been, we are at a juncture when the two countries are engaging in negotiations in the most earnest and constructive atmosphere," Kim told reporters upon arrival at Dulles International Airport.

"(We) will do our utmost to ensure that negotiations will be wrapped up well in a direction that serves (Korea's) national interests," he added.

/IANS