The Pentagon said on Monday the U.S. State Department had approved the sale of the weapons requested by Taiwan, including 108 General Dynamics Co M1A2T Abrams tanks and 250 Stinger missiles, which are manufactured by Raytheon <RTN.N.>.
Washington said the sales would not alter the basic military balance in the region, but Beijing, a major U.S. security rival with which Washington has been engaged in a year-long trade war, has demanded the deal be revoked.
China's latest statement came as Taiwanese President Tsai Ing-wen was in New York en route to visit four Caribbean allies, a trip that has also incensed China.
China's Foreign Ministry Spokesperson Geng Shuang said the U.S. arms sale constituted "a serious violation of international law and the basic norms governing international relations."
He also called it a serious violation of the "one-China" principle, under which the United States officially recognizes Beijing and not Taipei.
"To safeguard our national interests, China will impose sanctions on the U.S. enterprises involved in the above-mentioned arms sales to Taiwan," Geng said.
The U.S. State Department declined to comment and the U.S. firms involved in the Taiwan arms deal did not immediately respond. It was unclear what, if any, impact the Chinese move might have as U.S. defense contractors have been barred from dealings with Beijing since the 1989 Tiananmen Square massacre.
While its relations with Taiwan are technically unofficial, the United States government is required by law to assist Taiwan in its defense and is its main supplier of arms.
China deems Taiwan a wayward province and has never renounced the use of force to bring the island under its control.
On a visit to Budapest on Friday, China's top diplomat Wang Yi warned Washington it should "not play with fire" on the question of Taiwan
He said no foreign force could stop the reunification of China and no foreign force should try to intervene.
"We urge the U.S. to fully recognize the gravity of the Taiwan question ... (and) not to play with fire on the question of Taiwan," Wang told a news conference via an interpreter.
Tsai was last in the United States in March, but her transit stops this time will be unusually long and analysts said the extended stopovers, in which she will spend four nights on U.S. soil, emphasized the Trump administration's support for her at a time when she has been under increasing pressure from Beijing.
The U.S. State Department has said there has been no change in the U.S. one-China policy and that it allowed such transit stops "out of consideration for the safety, comfort, convenience and dignity of the passenger."
(Reporting by Beijing bureau and David Brunnstrom and Mike Stone in Washington and Krisztina Than in Budapest; Editing by Nick Macfie and Susan Thomas)