State Department officials have again raised concerns about European and Russian arms sales to China.
Undersecretary of State for Arms Control and International Security John Bolton says arms embargoes and other sanctions are important to send China a message that its record on human rights is unacceptable.
The European Union embargo on major arms sales to Beijing, imposed in 1989, is widely expected to be lifted this year - a move consistently opposed by the United States and Japan.
Speaking at a seminar in the Japanese capital Mr. Bolton said arms sales by the European Union and Russia are a "very grave concern" and could threaten strategic stability in East Asia.
The undersecretary said the Bush administration is most worried that sophisticated computer and communications technology, known as "battlefield management," will end up in the hands of the Chinese.
"American technology licensed to European companies might also find its way to China, so that we would, in effect, face our own technology being used against us," he said.
The EU sanctions were put in place in the wake of the 1989 massacre of pro-democracy demonstrators in Beijing's Tiananmen Square. The United States imposed a similar ban that same year, which remains in place.
Secretary of State Condoleezza Rice, also expressed concern Sunday about arms sales to China upsetting the military balance in East Asia.
President Bush has taken a tough stance against China, imposing sanctions against Beijing 62 times during his first four-year administration. By comparison, the Clinton administration, during its eight years, imposed fresh sanctions against China on only eight occasions.
The United States has called for China to crack down on numerous companies, most of which it says are owned or controlled by elements of the People's Liberation Army or the government. Washington says these companies have exported technology that can be used to make weapons of mass destruction to such nations as Pakistan, Iran, and Libya.
The Chinese government has insisted that such sanctions are unjustified, and calls the EU arms embargo a relic of the Cold War.