BEIJING, Dec. 18 (Xinhua) -- The United States should immediately cease its "dangerous act" of arming Taiwan, Chinese foreign ministry spokesperson Guo Jiakun said on Thursday when commenting on the U.S. approval of a package of arms sales worth around 11 billion U.S. dollars to the Taiwan region.

The U.S. blatantly announced its plan to sell massive advanced weapons to China's Taiwan region, which grossly violates the one-China principle and the three China-U.S. joint communiqués, Guo said at a regular news briefing.

The U.S. move infringes on China's sovereignty, security and territorial integrity, undermines peace and stability in the Taiwan Strait, and sends a gravely wrong signal to "Taiwan independence" separatist forces, Guo said.

"China firmly opposes and strongly condemns it," he said.

The "Taiwan independence" separatist forces on the island attempt to advance their "independence" agenda and resist reunification through military buildup, squander the taxpayers' money to purchase weapons, and even risk turning Taiwan into a "powder keg," he said.

Guo said such moves will not reverse the inevitable failure of "Taiwan independence," and will only push the Taiwan Strait into the danger of military conflict at a faster pace. For the United States, assisting the "independence" agenda by arming Taiwan will only backfire, and using Taiwan to contain China will never succeed, he added.

Noting that the Taiwan question is at the core of China's core interests, and is the first red line that must not be crossed in China-U.S. relations, Guo said no one shall underestimate the firm will and strong capability of the Chinese government and the Chinese people in safeguarding national sovereignty and territorial integrity.

China urges the United States to abide by the one-China principle and the three China-U.S. joint communiqués, act on its leaders' serious commitments, and immediately stop the dangerous act of arming Taiwan, he said.

China will take resolute and strong measures to defend its national sovereignty, security and territorial integrity, the spokesperson added.