South Korean President Moon Jae-in and US President Donald Trump will have a "pull aside"

rather than a formal bilateral meeting on the sidelines of a Group of 20 summit in Argentina this week, Reuters quoted the White House spokeswoman as saying Thursday.

Speaking to reporters aboard Air Force One en route to Buenos Aires, Sarah Sanders said Trump will have "pull asides" with both Moon and Turkish President Recep Tayyip Erdogan.

US National Security Adviser John Bolton earlier said that Moon and Trump will meet during the two-day summit starting Friday, and South Korea's presidential office later confirmed the plan.

Details of the time and place had yet to emerge.

"The White House has suggested we hold a summit with no one but translators, and we are in talks over the format, time and venue,"

an official of Cheong Wa Dae, the presidential office, said.

It will be the sixth bilateral meeting between Trump and Moon since both took office last year.

North Korea is expected to top the agenda amid stalled progress on dismantling the regime's nuclear weapons program.

North Korean leader Kim Jong-un committed to work toward "complete" denuclearization of the Korean Peninsula when he held historic summits with Moon and Trump this year.

But Washington and Pyongyang have yet to hold formal negotiations since the Trump-Kim summit in Singapore in June.

Trump has said he still expects to hold a second summit with Kim early next year. (Yonhap)