BEIJING - A Chinese mainland spokesperson on Thursday expressed firm opposition to the United States' arms sales to China's Taiwan region.

The move by the United States seriously violates the one-China principle and the three China-US joint communiques, particularly the August 17 Communique, said Ma Xiaoguang, a spokesperson for the State Council Taiwan Affairs Office, in response to a press inquiry on the decision of the United States to sell arms to Taiwan.

The move connives at and supports separatists seeking "Taiwan independence," and undermines peace and stability across the Taiwan Straits, Ma added.

"We urge the United States to abide by the one-China principle and the three China-US joint communiques, and to cease arms sales to and military contact with Taiwan," Ma said.

Ma also warned Taiwan's Democratic Progressive Party authorities that any attempt to use force to resist reunification or collude with external forces to seek "Taiwan independence" is doomed to fail.