U.S. State Secretary Hillary Clinton has met with Chinese President Hu Jintao.
As the talks began, Clinton, who is in Beijing for two days, said bilateral ties were on a "solid basis."
At a joint news conference with Clinton, Chinese Foreign Minister Yang Jiechi promised that there would "never be issues" in the South China Sea.
Earlier in Indonesia, Clinton called on members of the Association of Southeast Asian Nations (ASEAN) to stand together on the territorial disputes in the South China Sea.
China has competing territorial claims with four ASEAN member-states.
Clinton is on an Asian tour that has also taken her to the Cook Islands.
A planned meeting with Xi Jinping, widely expected to be China's next president, has been canceled for unspecified reasons.
Meanwhile, reports from Japan say the government has reached a deal to buy disputed islands in the East China Sea.
There was no confirmation from officials, but the reports were carried by major Japanese media outlets.
Tensions over the islands -- known as Senkaku in Japan and Daioyu in China -- have flared since April, when Tokyo's governor announced plans to buy them from a private owner.
Japan controls the islands, but both China and Taiwan claim them.
The Kyodo news agency, citing unidentified government sources, reported that the Japanese government will pay $26 million to buy three of the five main islands, saying an agreement was reached with the Japanese owner on September 3.
The “Asahi” and “Yomiuri” newspapers reported that the cabinet will approve the deal in the middle of September.
China does not recognize the Japanese family's ownership of the islands, so the deal would not affect China's claim to them.
Based on reporting by AP and AFP