Undersecretary of State for Security and Arms Control John Holum made no comment to reporters as he entered his hotel in the Chinese capital.

His visit is aimed at paving the way for the full resumption of non-proliferation talks -- broken off after the May 7, 1999 embassy bombing.

Chinese foreign ministry spokesman Sun Yuxi welcomed the visits by Holum and US Defense Secretary Willian Cohen next week, saying they were important for maintaining a healthy relationship between the two sides.

"They not only serve the fundamental interests of the two countries but are also very important and of far reaching significance for maintaining regional and global interests," he said.

But the spokesman went on to criticise the United States over the bombing of the embassy in Yugoslavia and Washington's proposed National Missile Defense (NMD) system and its propsed Theatre Missile Defense (TMD) system with Japan.

"We are still demanding that the US side face the severity of this bombing incident and carry out a full investigation into this matter leading to a satisfactory explanation," he said.

The bombing, which killed three and injured some 20 embassy staff, "was a gross violation of Chinese sovereignty, greatly hurt the feelings of the Chinese people and undermined China-US relations."

The visit by Cohen is the first visit by a US defense secretary since the bombing, which the United States has called a "tragic mistake" and paid 32.5 million dollars in compensation.

It follows a visit by US Secretary of State Madeleine Albright to Beijing last month.

During the talks the United States is expected to raise objections to the sale of weapons and missile technology to Iran and Pakistan, while China will object to US weapons sales to Taiwan, diplomats said.

The United States is also expected to outline its hopes of amending the 1972 Anti-ballistic Missile (ABM) Treaty signed between Washington and Moscow, a move deemed necessary to clear the United States of its international obligations to refrain from developing new missile systems.

"Regarding the missile defense plan we believe it is against the trend of the times and is not conducive to the international disarmament and arms control efforts and will have a negative impact on the global and regional strategic balance and stability," Sun said.

A proposed joint US-Japan theater missile defense system will "dramatically raise the legitimate defense needs" of other countries in the region and undermine peace and security in the Asian region.

"If any country would like to include Taiwan in a TMD system that will constitute a gross violation of China's sovereignty and territorial integrity and shall meet with the strong opposition of the Chinese side," he added.

Sun further reiterated China's support for Russian opposition to amending the AMB Treaty, saying "the two sides have already started cooperation in this regard and will continue to intensify cooperation in further maintaining the strategic balance in the world."

With the resumption of Sino-US security and arms control talks and high-level military exchanges, now all that is lacking between the two countries is the resumption of their human rights dialogue.

"Its our belief that the responsibility for the break down of the human rights dialogue does not lie with the Chinese side, we hope the United States will take concrete actions to enable us to resume," Sun said.