WASHINGTON, June 25 -- The just-concluded China-U.S. annual high-level talks seemed to have accomplished the goals of managing their tensions and paving the way for the state visit to the U.S. by Chinese President Xi Jinping, a U.S. China expert said Thursday.

China and the U.S. ended the two-day Seventh Strategic and Economic Dialogue (S&ED) and Sixth High-level Consultation on People-to-People Exchange (CPE) Wednesday with a number of results and agreements on boosting cooperation on wide-ranging bilateral, regional and international issues.

"Managing tensions and forging an agenda for the Xi Jinping's state visit seem to be getting accomplished, although many specific outcomes will probably be kept under wraps until September," Douglas Paal, vice president for studies at the Carnegie Endowment for International Peace, told Xinhua in an interview.

"Moreover, away from the S&ED forums, China is lowering the rhetoric and winding up reclamation in the South China Sea, causing the U.S. to reciprocate," Paal noted.

Indeed, despite the recent disputes over the South China Sea and cyber security, both sides sounded upbeat when they met to discuss issues of mutual concern and explore new areas of future cooperation.

Speaking at the opening ceremony, U.S. Vice President Joe Biden surprised many by applauding China for being a "responsible stakeholder" in many ways in the past ten years through cooperating with the U.S. on dealing with a lot of regional and international issues.

"That surprised me, because it was a term from the previous Bush administration that the Obama team has not used," Paal said in commenting the term of "responsible stakeholder," which was invented ten years ago by then Deputy Secretary of State Robert Zoellick to urge China to strengthen the international system that has enabled its success.

"I think it was deployed in order to continue on and say China should also be a 'responsible competitor,' which I guess to mean that China should exercise greater restraint as it expands its capabilities," Paal said.

One of the major tasks of the latest round of talks was to prepare for the Xi visit in fall, with both sides pledging to make all efforts to turn it into a big success.

Chinese Vice Premier Wang Yang, speaking at the closing ceremony, said that the success of this round of economic dialogue has provided a stronger foundation for the healthy and stable growth of the China-U.S. ties and laid the ground work for the economic agenda of Xi's upcoming visit to the U.S.

Chinese State Councilor Yang Jiechi said that the two sides had agreed to deepen practical cooperation, enhance interaction in the Asia-Pacific, handle regional hotspots and global challenges and manage differences in a constructive fashion.

U.S. Secretary of State John Kerry said the depth and breadth of discussion at this year's S&ED reflected a joint U.S.-China commitment to cooperating in areas of common interest and seeking constructive solutions where the two sides have differences.

As the two sides are actively preparing for the Xi visit, they are expected to keep tuning down their rhetoric even there will be new accidents taking place, Paal believed.

He said he definitely expected "the tone to remain deliberately subdued through September," though accidents can and will happen.

"I have the feeling that the officials on both sides are making every effort to turn the September visit into a big success. Doing so requires a lot of restraint both in words and behavior," Paal said.

He said that the Xi visit is very important, because "it is likely to set the tone for the next year and a half until a new administration enters office in Washington."

"The US will be preoccupied and China will be busy strengthening itself," Paal said, referring to the fact that the U. S. will enter a new circle of election politics during which China will easily be victimized.

Talking about the achievements of the two-day intensive talks, Paal said that though he did not yet see the full lists of results, at least he thought the talks on climate change and energy cooperate were "constructive."

The two sides indeed pledged to further their cooperation on climate change to ensure the Paris climate change conference to be held at the year end will achieve a successfully global agreement.

On the economic front, the macro economic coordination continues substantially, marking the more successful side of the S& ED process, Paal said, adding that the two sides also apparently agreed to expand cooperation on international issues, such as Afghanistan, Sudan, Iraq, and others.

Notably, it was agreed that the two sides will speed up the negotiation on a crucial mutual investment treaty and exchange the second offers of the "negative lists" in early September, just ahead of the Xi visit.