China said yesterday it was "deeply concerned" at comments from President Bush that he would "do whatever it took" to defend Taiwan.
A Foreign Ministry spokeswoman said Mr Bush was leading his country "on a dangerous road" and his comments would damage already strained relations.
The spokeswoman said the President's comments - made in a US television interview - were a violation of agreements that formed the basis of diplomatic relations between China and the US. Mr Bush's comments came after Washington unveiled the biggest arms package in a decade for Taiwan.
His "erroneous statement" seriously violated the three Sino-US joint communiques and relevant US commitments as well as undermining peace and stability across the Taiwan Strait, the Foreign Ministry spokeswoman said.
"Taiwan is a part of China, not a protectorate of any foreign country," she added, urging Washington to "correct its mistakes and stop interfering in Chinese internal affairs".
China has threatened to attack Taiwan if it declares independence or drags its feet on reunification talks.
China's reaction was, according to analysts, restrained when compared to inflammatory Chinese rhetoric over presidential elections in Taiwan last year and the April 1st collision between a US spy plane and a Chinese jet fighter.
They said China was also uncharacteristically subdued in its protests over a US decision to issue a visa to former president, Mr Lee Teng-hui of Taiwan last week.
Yesterday's morning state newspapers did not even mention Mr Bush's comments on defending Taiwan. The online edition of the People's Daily later highlighted his subsequent remarks toning down his position.
"US President Bush has clarified his earlier remarks that the United States would do `whatever it took' to help Taiwan defend itself by saying US policy on Taiwan had not changed," it said.
It stressed that Mr Bush had reaffirmed his commitment to the "one China" principle, and told Taiwan not to declare independence and hoped for a peaceful resolution of the issue.
The English-language China Radio International also noted that Mr Bush had reaffirmed his commitment to the 1979 Taiwan Relations Act, which also leaves ambiguous whether the US would come to Taiwan's aid in the event of hostilities.
China has executed another 30 people, state media reported in Beijing yesterday, raising to more than 400 the number of people put to death in April as part of a nationwide crackdown on crime.