"It is through the tireless efforts of organizations like yours that the bonds between our two countries remain strong and vibrant," Harris said in the speech.

"As we go forward to meet the challenges of maintaining peace, stability and prosperity across the peninsula and beyond, we go together -- shoulder to shoulder," he said.

Concerns have arisen over possible friction between the allies following Seoul's decision to end a military information-sharing pact with Japan, despite Washington's appeals to keep the accord seen as a rare platform for trilateral cooperation between the South, the United States and Japan.

In August, South Korea announced its decision to end the General Security of Military Information Agreement after Japan imposed export curbs on South Korea in apparent retaliation against the top court's ruling on wartime forced labor. (Yonhap)