WASHINGTON (REUTERS) - China summoned the US charge d'affaires in Beijing to protest against the US administration's authorisation of US$1.83 billion (S$2.5 billion) arms sales to Taiwan and said it would impose sanctions on the firms involved, China's state news agency Xinhua reported.

"Taiwan is an inalienable part of China's territory. China strongly opposes the US arms sale to Taiwan," Xinhua quoted Vice-Foreign Minister Zheng Zeguang, who summoned US envoy Kaye Lee, as saying.

Xinhua said Mr Zheng described the US sales authorisation announced on Wednesday (Dec 16) as going against international law and basic norms of international relations and said that they "severely" harmed China's sovereignty and security.

"To safeguard our national interests, China has decided to take necessary measures, including imposing sanctions against the companies involved in the arms sale," Mr Zheng said.