A Chinese general said Beijing might respond with nuclear weapons if the United States attacked China in a conflict over Taiwan (search), news reports said Friday.

The State Department rejected the warning as "highly irresponsible."

The exchange could add to tensions with Washington at a time of U.S. worries about China's military buildup and the proposed takeover of the oil company Unocal Corp (search). by a Chinese state-run company.

"If the Americans draw their missiles and position-guided ammunition into the target zone on China's territory, I think we will have to respond with nuclear weapons," Maj. Gen. Zhu Chenghu, a dean at China's National Defense University, told visiting Hong Kong-based reporters. His remarks were reported by The Asian Wall Street Journal and The Financial Times.

Zhu stressed he was expressing a personal view, not official policy, and was confident that China and the United States would not go to war, the reports said. While Zhu is a serving officer, he isn't involved in policymaking.

State Department spokesman Sean McCormack said he hoped that the comments did not reflect the views of the Chinese government. From what he had seen of the quotes, McCormack said, "I would say they are highly irresponsible."

The Chinese Foreign Ministry didn't respond to requests for comment on the general's remarks. A woman who answered the phone at the protocol office of the Defense Ministry said it had no comment. She refused to give her name.

China claims Taiwan, which split from the mainland in 1949, as part of its territory and has threatened to invade if the self-governing island declares formal independence or puts off talks on unification.

Also Friday, the visiting president of the European Commission (search), Jose Manuel Barroso, called on Beijing to open direct talks with Taiwan, saying it would help to promote peace in East Asia.

"The international community would welcome China starting a direct dialogue with Taiwan as a sign of great maturity," Barroso said in a speech at the Chinese Academy of Social Sciences, the government's main think tank.

Zhu was responding to a question about how China might react to U.S. involvement in a conflict with Taiwan, the Journal said. The United States is Taiwan's biggest arms supplier and could be drawn into fighting to help defend the island.

"If the Americans are determined to interfere ... we will be determined to respond, and we Chinese will prepare ourselves for the destruction of all cities east of Xi'an," a major city in central China, Zhu said.

"Of course the Americans will have to be prepared that hundreds of, or two hundreds of, (or) even more cities will be destroyed by the Chinese," he said.

The general said his comments were "my assessment, not the policy of the government," the Journal said.

China exploded its first nuclear weapon in 1964 and has an arsenal of missiles that can carry nuclear warheads.

China has a "no first strike" nuclear policy, but according to the Journal, Zhu said he believed that applied to non-nuclear powers and could be changed.

The general said China has no intention of getting into an arms race with the United States, noting the experience of the former Soviet Union as evidence of the futility of doing so, the report said.