"We've seen a number of trends that indicate they're not as committed or haven't been as committed to the notion of a peaceful process as they have been in the past," Cheney said Friday in an interview on CNN's "Larry King Live."
The comments came at the end of a week during which the President Bush okayed the sale of submarines, destroyers and planes to Taiwan. He deferred the sale of a high-tech combat radar system, but the decision angered China nonetheless.
Chinese anger increased when Mr. Bush said U.S. military force would be an option if Taiwan were invaded, breaking decades of ambiguity on how Washington would respond to a Chinese invasion of the island that separated from the mainland in 1949, but which Beijing claims as part of its territory.
Mr. Bush later clarified his comments, saying that he was not signaling any change in policy. But the weapons sale and the president's comments came amid heightened tension between China and the United States.
The relationship has been strained by disagreement over the collision of a U.S. spy plane and a Chinese jet, American plans for a missile defense and criticism of China's human rights record.
The vice president cited a Chinese buildup of missiles aimed at Taiwan and a "much more aggressive" treatment of U.S. surveillance aircraft off their coast, something the Clinton administration warned China against in December.
"Subsequent to that, we had the accident where they actually flew into one of our planes, killed their pilot and nearly killed 24 of ours," Cheney said.
"What the president has done is to reiterate that very strong determination on our part that there should not be a resort to force by the mainland in order to try to pull Taiwan closer," Cheney said.
China said Friday that U.S. weapons cannot ensure Taiwan's security and will not deter China's determination to unify with the island.
"There is only one China in the world. Taiwan is part of China. It is not a protectorate of any foreign country," Foreign Ministry spokeswoman Zhang Qiyue said at a news conference Thursday.
Taiwan Affairs Office spokesman Zhang Mingqing Friday rebuked Washington for offering to sell Taiwan high-tech weapons, saying it would worsen U.S.-China relations and increase tensions in the Taiwan Strait.
"Chinese have never knuckled under to foreign pressure. Nothing can stop the Chinese people realizing the great task of unifying the national territory," Zhang said at a news conference.
"Relying on foreigners and their guns to ensure security will never work," he said.
Zhang reiterated the government's view that arms sales to Taiwan infringe on Chinese sovereignty and violate U.S. commitments to Beijing.
"The Taiwan issue is China's internal issue," Zhang said.
Mr. Bush's comments Wednesday may have worried Chinese leaders who believe he has scrapped Washington's past ambiguity over whether it would use force to defend Taiwan, said Joseph Cheng, a China scholar in Hong Kong.
But Beijing's response will be tempered by a desire to maintain peace with its neighbors, said Cheng, director of the Contemporary China Research Center at City University.
"They are certainly realistic in trying to secure a peaceful international environment to concentrate on economic development and they understand they need a good relationship with the United States," Cheng said in a telephone interview.
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