Robert Gates tours China nuclear warfare headquarters
US Defence Secretary Robert Gates has visited China's nuclear warfare headquarters, at the end of a four-day visit to try to mend relations between the two militaries.
"There was a discussion of nuclear strategy," including China's policy of not using nuclear weapons pre-emptively, Mr Gates said.
Officials from both countries praised the visit as a success.
Beijing froze military ties last year because of a US arms sales to Taiwan.
The rare view of China's nuclear and missile arsenal was given on a trip to the Second Artillery Corps of the People's Liberation Army (PLA) headquarters.
Both the US and China have long-range missiles capable of reaching each other's shores, but both have said they do not intend to use them.
The visit by Mr Gates to China was pronounced a success by both Beijing and Mr Gates.
"We believe exchanges with the US in all kinds of fields are beneficial. They'll add to our mutual trust and eliminate misunderstanding and miscalculations," said Guan Youfei, deputy chief of the Defence Ministry's foreign affairs office.
"The visit is a move to develop healthier and more stable relations between the two military establishments," he said.
Mr Gates said the commander of the nuclear headquarters, General Jing Zhiyuan, had accepted an invitation to US strategic Command headquarters in Nebraska.
"I think the discussions were very productive and set the stage for taking the military-to-military relationship to the next level," he said.
Mr Gates' visit comes ahead of a trip by Chinese President Hu Jintao to Washington next week.
China has agreed to more direct military co-operation with the US but it remains unclear how open and collegial such exchanges will be.
Mr Gates has said he wanted to convene a new round of military talks in the first half of this year to cover nuclear, missile defence, cyberwarfare and the military uses of space alongside the current focus on maritime issues.
Last year, tensions increased significantly over a series of maritime disputes, with the US supporting South East Asian concerns at China's re-stated claim to the South China Sea.