China sanctions five US defence firms over Taiwan arms sales
China has announced sanctions on five Western defence firms over the latest round of US arms sales to Taiwan.
The announcement comes as Taiwan prepares to hold presidential and parliamentary elections on 13 January.
US weapons sales to Taiwan are a frequent source of tension between Beijing and Washington.
China views democratically governed Taiwan as its territory, a claim Taiwan's government rejects.
Last month, the US State Department approved a $300m (£236m) sale of equipment to help maintain Taiwan's tactical information systems.
The Chinese Foreign Ministry said in a statement on Sunday that the sanctions were "In response to these gravely wrong actions taken by the US".
It also said the recent arms sales "seriously harm China's sovereignty and security interests, undermine the peace and stability across the Taiwan Strait".
The companies being sanctioned were named as BAE Systems Land and Armament, Alliant Techsystems Operation, AeroVironment, ViaSat and Data Link Solutions.
China will freeze the assets of the companies and ban people and organisations in China from engaging them, the Foreign Ministry said.
The BBC has contacted the US embassy in Beijing for comment.
Beijing has ramped up its pressure on Taiwan ahead of the elections that could redefine the island's relationship with China.
In his annual New Year's Eve address, Chinese President Xi Jinping reiterated his claim that Taiwan would "surely be reunified" with China.
He also struck a stronger tone than last year's message, when he spoke about Taiwan being part of the "same family".
China sees the self-ruled island of 23 million as a breakaway province that will eventually be under Beijing's control. Taiwan considers itself distinct from the Chinese mainland, with its own constitution and democratically elected leaders.