BEIJING, Dec. 13 (Xinhua) -- The Chinese mainland resolutely opposes any official or military exchanges between the United States and Taiwan, a Chinese mainland spokesperson said Wednesday.

An Fengshan, spokesperson for the Taiwan Affairs Office of the State Council, said at a press conference that the Taiwan issue is China's internal affair.

"Any attempt to undermine the country's sovereignty and territorial integrity is bound to incur the Chinese people's opposition and will not succeed," An said.

The mainland will uphold "peaceful reunification" and the "one country, two systems" principle, promote peaceful development of cross-Strait relations and peaceful reunification, according to a press conference by the Ministry of Foreign Affairs earlier this week.

The Chinese mainland urged the United States to abide by the one-China policy and the three China-U.S. joint communiques, and cautiously and properly handle the Taiwan issue.