WASHINGTON, June 30 -- A close cooperation between China and the United States, two global leaders, would be tremendously beneficial to the entire international system, a U.S. expert said Monday.

China and the United States have had some notable successes in developing a mature relationship between two major countries, Ted Galen Carpenter, a senior fellow for defense and foreign policy studies at the Cato Institute, said in an interview with Xinhua.

Carpenter said cooperation has increased on the issue of the Democratic People's Republic of Korea (DPRK) and the broader topic of nuclear proliferation between the U.S. and China. The cooperation has also contributed to progress on the Iranian nuclear issue.

He noted there is growing policy coordination regarding global economic issues. "That cooperation helped ease the duration and pain of the global great recession and led to the still evolving recovery," he said.

Indeed, China and the United States are positioned to be the global leaders on economic and security issues, and "close cooperation would be tremendously beneficial to the entire international system," Carpenter said.

"Conversely, an increase in bilateral tensions has an alarming potential to disrupt the global economy and create the specter of greater instability and violence," he said.

Talking about Chinese President Xi Jinping's state visit to the U.S. in September, Carpenter said all of the issues above, along with the thorny topic of cyber security, will be major topics at the upcoming summit meeting.

"I expect both leaders to highlight the areas of agreement between the two countries and minimize areas of disagreement," he said, "Thus, the atmospherics around the meeting should be cordial and positive."

Foreseeing the Sino-U.S. relationship's future development, Carpenter said "I hope that the relationship will become closer, but I fear that except for the economic dimension, the forces of divergence are becoming stronger."

He said Washington seems to be solidly behind its ally, Japan, regarding that controversy, and that stance is likely to increase U.S.-China tensions over the medium and long term.

He noted that there are also signs that the Taiwan issue, which has been mercifully quiet since Ma Ying-jeou's election victory in 2008, may be growing in intensity. The recent U.S. Senate resolution urging the Obama administration to include Taiwan in upcoming naval exercises is just one sign of possible trouble.

Carpenter said that Washington's deepening involvement in the South China Seadispute is now a major irritant in bilateral relations, as Chinese leaders see the U.S. actions as directed against China.

The Obama administration's behavior is also emboldening other claimants, especially the Philippinesand Vietnam, making it more difficult to find a solution to the underlying territorial controversies, he said.

"If U.S. leaders continue on this path, they will not exert power over China, they will needlessly antagonize China and increase overall tensions in East Asia," Carpenter warned.

He stressed that all of the issues mentioned above pose challenges to the bilateral relationship. If they can be overcome, the potential for cooperation between China and the U.S. on all other matters will be impressive.