From Reuters, via Wired.com:
U.S. Deputy Secretary of State Robert Zoellick told China on Wednesday it should take concrete steps to assure the world it will use its power responsibly and said Beijing’s approach to Iran would prove its seriousness on combating nuclear proliferation.
The “essential question” for the United States and the world was “how will China use its influence” because the answer would have a profound effect on international development for years to come, he said.
In a speech to the National Committee on U.S.-China Relations, which promotes ties between the two countries, Zoellick acknowledged that “many Americans worry that the Chinese dragon will be a firebreather. There is a caldron of anxiety about China.”
See also “State Department: US-China relationship complex” from China Daily and “U.S. Says China Must Address Its Intentions” from the Washington Post.