China announced sanctions on Sunday against five US defense firms in response to their involvement in arms sales to Taiwan, which Beijing deems part of its territory.

Last month, the US State Department approved a $300-million arms package to strengthen Taipei's joint battle command and control system, prompting Beijing to say it would take unspecified "countermeasures" against the companies involved.

China's Foreign Ministry on Sunday named those companies as BAE Systems Land and Armament, Alliant Techsystems Operation, AeroVironment, ViaSat, and Data Link Solutions.

"The countermeasures consist of freezing the properties of those companies in China, including their movable and immovable property, and prohibiting organizations and individuals in China from transactions and cooperation with them," the ministry indicated.

"The US arms sales to China's Taiwan region... seriously harm China's sovereignty and security interests," it stressed.

In his New Year's address, Chinese President Xi Jinping adamantly declared the reunification of Taiwan inevitable. 

"Compatriots on both sides of the Taiwan Strait should be bound by a common sense of purpose and share in the glory of the rejuvenation of the Chinese nation," Xi said, consistent with previous sentiments of a one family people divided by a strait.

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