Huawei has been the target of a broad US crackdown, including allegations it sold telecommunications equipment that could be used by China's Communist Party for spying.

In a 13-count indictment in Brooklyn, New York, the government alleged Huawei, two affiliated companies and its chief financial officer, engaged in fraud and conspiracy in connection with deals in Iran.

A 10-count indictment in Washington state accused the company of stealing trade secrets from T-Mobile and offering bonuses to employees who succeeded in nicking technology from rivals.

T-Mobile sued Huawei and its US-based unit, Huawei Device USA, in 2014, and three years later, a federal jury in Seattle found Huawei liable for both breach of contract and misappropriation of trade secrets.

The claims regarding the theft of its technology caught the attention of federal authorities in the Western District of Washington.

T-Mobile said Huawei sent its engineers to T-Mobile's Bellevue, Washington, facility to see a robot, called "Tappy" which simulates smartphone use. T-Mobile said in its lawsuit that Huawei used stolen parts from the robot to "develop, improve and troubleshoot its own robot".