Commenting on reports the new Taiwanese leader would pass through the United States during his trip, Chinese Foreign Ministry spokesman Liu Jianchao said his country will "always oppose the United States to have official contacts in any form with the Taiwan authority," the state-run news agency Xinhua reported.

China has always claimed Taiwan as part of its territory.

Ma, who was elected in March with a big margin, had campaigned for closer ties and improved trade with the Mainland.

The Chinese spokesman used the occasion to stress that his government's one-China principle is unchangeable no matter what changes occur in the Taiwan Straits situation.

Liu said he hoped the United States would abide by its one-China commitment and "solve the issue cautiously and properly," the Xinhua report said.