The delegation also met US Secretary of State Hillary Clinton and several members of the US Congress.

Both Chen and Mullen emphasized that agreements were reached within the framework of building a "US-China cooperative partnership based on mutual respect and mutual benefit", a consensus that President Hu Jintao and US President Barack Obama attained during Hu's official visit to the US in January.

Chen and Mullen highlighted the fact that "a healthy, stable and reliable military-to-military relationship is an important part of the China-US relationship".

Their talks provided an "opportunity to validate our assumptions of each other so we can make adjustments accordingly", Mullen said.

Chen played down Chinese military advances on his trip, telling an audience of US military officers and faculty members at the National Defense University that the PLA lagged at least 20 years behind developed Western nations.

Chen made a similar point later at the Pentagon news conference.

"I can tell you that China does not have the capability to challenge the US," he said, adding that China's wealth and military strength pales in comparison with that of the US. China's navy is 20 years behind the US navy. he said.

"To be honest, I feel very sad after visiting (the US), because I think, I feel and I know, how poor our equipment is and how underdeveloped we remain," Chen said.

"Although China's defense and military development has come a long way in recent years, a gaping gap between you and us remains," Chen said.

"China never intends to challenge the US," he added.

Mutual trust and especially mutual respect and accommodation of each other's core interests are essential to China-US military ties, Chen said.

Chen and Mullen discussed US reconnaissance activities in waters close to China.

The two military chiefs also stressed shared concerns over such issues as nuclear proliferation, terrorism, climate change, energy security and piracy, Mullen said.

Above all, "what he (Chen) and I both talked about is the future, a peaceful future, a better one for our children and grandchildren", Mullen said.

"That (future) does not include conflict between China and the US."

Chen extended an invitation to Mullen and his wife to visit China, an invitation that Mullen accepted.

Liu Lin, an expert on world military studies with the PLA Academy of Military Sciences, said US politicians have a tradition of overreacting to the Chinese mainland's military deployment across the Taiwan Straits.

"It is a domestic affair. But the US uses it as an excuse for arms sales to Taiwan," Liu said.

Yao Yunzhu, a researcher at the same academy, said it is time for Washington to "review whether the Taiwan Relations Act, passed more than 30 years ago, is still relevant (in dealing with the Chinese island)".