President Park Geun-hye stressed the need Tuesday for Northeast Asian nations to redouble efforts to build trust in order to foster peace and co-prosperity in the region long dogged by history and territorial disputes.

"Northeast Asia has a long way to go to build trust. It's because cooperation among regional countries are restricted by longstanding conflicts over history and territory," she said in a message for a Seoul forum on regional peace and stability. It was read by Vice Foreign Minister Lim Sung-nam.

Park has been pushing for the Northeast Asia Peace and Cooperation Initiative aimed at promoting peace and harmony in the region on a step-by-step basis through a multilateral cooperative body.

Park noted dialogue among key players in Northeast Asia has been brisker than ever in autumn this year.

South Korea and the U.S. held summit talks earlier this month following South Korea-China and the U.S.-China summits a month earlier, she cited.

"In a few days, the leaders of South Korea, Japan and China will gather in one place," Park said.

She was referring to an annual trilateral summit expected to resume in Seoul this weekend.

But territorial tensions have soared again as the U.S. sent a warship near one of China's artificial islets in the South China Sea in protest against Beijing's growing assertiveness in its territorial spats with Southeast Asian countries.

The USS Lassen sailed through waters within 12-nautical miles of Subi Reef, according to Pentagon officials.

China immediately denounced the U.S. move.

Park did not directly mention the latest stand-off, instead saying a crisis always gives rise to a new opportunity.

"Now is the very time to seize the chance for peace and cooperation," she said.

Formally, South Korea responded prudently to the U.S. action against China.

Asked about the issue in a regular press briefing, the Foreign Ministry's spokesman Noh Kwang-il said, "We are well aware of such media reports. We are trying to figure out the relevant facts."

On China's construction of artificial islands in the South China Sea, he reiterated Seoul's basic position.

"Protecting the freedom of navigation and flights as well as the implementation of the Declaration on the Conduct of Parties in the South China Sea is important to peace and stability in the region," Noh said.

He pointed out that the South China Sea is a major sea lane heavily affecting South Korean interests. (Yonhap)