Huawei is launching legal action against the US government over a ban that would bar people from accessing its products.
The Chinese tech giant filed a lawsuit in Texas over the law that also labels the company a security risk.
Huawei, China's first global tech brand, is at the centre of US-Chinese tensions over technology competition and cyber-spying.
"We are compelled to take this legal action as a proper and last resort," the company's rotating chairman, Guo Ping, said.
The company has spent years trying to put to rest accusations it facilitates spying or is controlled by the ruling Communist Party.
Mr Guo said the ban would limit competition, slowing the roll out of fifth-generation communications and raising consumer prices.
US authorities "have hacked our servers and stolen our emails" but have presented no evidence to support their security claims, he said.
He complained that Washington was "sparing no effort to smear" the company
The company is challenging the US law as an unconstitutional "bill of attainder", or a measure that targets a specific individual for penalties without a trial.
Huawei said this infringes its due process rights and improperly has Congress play the role of a court.
The ban is "based on numerous false, unproven and untested propositions," said Song Liuping, the company's chief legal officer.
"Huawei has an excellent security record and programme. No contrary evidence has been offered."
