South Koreans expressed mixed views Thursday after a senior U.S. diplomat called for South Korea to play a role in speaking out against China's territorial claims in the South China Sea.

On Wednesday, U.S. Assistant Secretary of State Daniel Russel told a seminar in Washington that South Korea should play a larger role in the territorial dispute as a major stakeholder in the international order.

"The fact that, like the United States, the Republic of Korea is not a claimant, in my view, gives Seoul all the more reason to speak out because it is speaking not in its self-interest, but speaking in support of universal principles and the rule of law," he said.

China's land reclamation projects in the South China Sea have irked other countries that lay claim to the waters, including the Philippines and Vietnam, as well as the United States, which views them as a threat to regional stability.

In a post on South Korea's largest portal site, Naver, one Internet user protested the U.S. call, saying Washington should speak out against Japan's claims to South Korea's easternmost islets of Dokdo as it too is not a claimant in the row.

Another user demanded that the U.S. first press Japan to recognize Dokdo as Korean territory and acknowledge the Japanese military's forced mobilization of Korean women as sex slaves during World War II.

Some called for a neutral stance, while others proposed an open-minded approach.

"How can we ask other countries to support us if we turn our backs on their difficulties? Of course we must support the U.S.," wrote one Naver user. (Yonhap)