GYEONGJU, South Korea - U.S. participation at the Asia-Pacific Economic Cooperation (APEC) forum this week in South Korea has been "very strong and robust", U.S. Senior Official to APEC Casey Mace said on Friday.

Mace made the comment at a briefing on the sidelines of the gathering after being asked about why U.S. President Donald Trump had left South Korea before the start of the leaders' summit.