China says its Vice Foreign Minister Xie Feng lodged a strong protest with the US embassy in Beijing on Sunday against the downing of a Chinese balloon.

A US military jet shot down the balloon off the coast of South Carolina on Saturday.

Xie stressed that nothing could be done about the unmanned civilian airship straying into US airspace, calling it an unexpected and accidental incident. He said what happened is very clear, and China will not forgive the distortion and the slanderous remarks.

Xie denounced the US action, saying it has seriously damaged efforts and the process for stabilizing ties between the two countries following the November bilateral summit in Indonesia.

He urged the United States not to take further actions that could harm China's interests and escalate tensions.

Xie also said Beijing will protect the legitimate rights of Chinese firms.