The nominee to be the U.S. ambassdor to the Philippines said Wednesday that he will work closely with Manila to help the Southeast Asian ally reduce tensions in the South China Sea and better monitor the waters off their shores.

Amb. Sung Kim made the remark during his Senate confirmation hearing as tensions have spiked between the U.S. and China in the wake of an international tribunal's ruling that rejected China's territorial claims to most of the South China Sea in a victory for the Philippines and other countries locked in maritime disputes with Beijing.

China immediately rejected the ruling, saying it does not accept or recognize it.

"If confirmed, I will work with Philippine President (Rodrigo) Duterte and his new administration to ensure our security cooperation remains strong and effective," Kim told the hearing.

"This includes supporting Philippine efforts to peacefully reduce tensions in the South China Sea and help the Philippine Armed Forces better monitor the seas off their shores."

Kim also said the U.S. commitment to defend the Philippines is "ironclad and unwavering."

Kim, special representative for North Korea policy who concurrently serves as deputy assistant secretary for Korea, was nominated in May to be ambassador to the Philippines.

The confirmation hearing for Kim ended with only a couple of questions, with Sen. Cory Gardner (R-CO), chairman of the hearing, calling Kim and two other nominees "well qualified." But it is unclear when his nomination will be officially confirmed as Congress goes into a seven-week recess at the end of this week. (Yonhap)