A joint statement issued by US President Joe Biden and South Korean President Moon Jae-in has stressed the importance of the freedom of navigation in the South China Sea and human rights but without directly mentioning China.
Biden and Moon issued a joint statement after holding a summit in Washington on Friday.
The statement says the leaders "emphasize the importance of preserving peace and stability in the Taiwan Strait" in an apparent effort to keep China in check.
The statement also says the two countries pledge to respect international law, including freedom of navigation and overflight in the South China Sea and beyond.
It says the two countries "share our intent to promote human rights and rule of law issues, both at home and abroad."
However, there was no direct mention of China in the document, in marked contrast with the Japan-US joint statement issued last month, following a summit meeting between Biden and Japanese Prime Minister Suga Yoshihide.
In the Japan-US joint statement, the two countries expressed objection to what they saw as China's unlawful maritime claims and activities in the South China Sea. It also said the two countries share serious concerns regarding the human rights situation in Hong Kong and the Xinjiang Uyghur Autonomous Region.
Ahead of Friday's summit, diplomatic sources on both sides told NHK that China would be a major topic in the talks and a focus of attention would be how to refer to China in an envisioned joint statement.
Observers say while the US side sought to put forward a strong message against China, South Korea may have been reluctant to do so, out of concern for provoking China.
The Biden administration hopes to strengthen coordination between the US, Japan and South Korea in an effort to counter China. However, the US-South Korea joint statement has revealed some differences among the three parties in how to deal with China.