BEIJING (AP) _ China on Monday rebuked Taiwanese President Chen Shui-bian, saying he showed no sincerity in his inauguration speech about improving relations with Beijing.

The remarks by the Cabinet's Taiwan Affairs Office were the first response by China to Chen's speech and set a confrontational tone for the beginning of his second term.

Office spokesman Zhang Mingqing China faulted the Taiwanese president for refusing to concede that Taiwan was a part of the Chinese nation _ the position China has laid down as its basic demand for improving ties.

``Chen Shui-bian has shown no sincerity to improve relations,'' Zhang said.

``If he has sincerity to improve relations, he must acknowledge that Taiwan and China together make up a single country,'' Zhang said.

Zhang referred repeatedly to China's threat to use force to unify with the island it claims as its sovereign territory, saying China would ``pay any price'' to safeguard its territory.

``He has not reduced the possibility of conflict. The threats to peace and stability in the Taiwan Strait continues to exist,'' Zhang said.

China and Taiwan split amid civil war in 1949.