US authorities are in the "advanced" stages of a criminal probe that could result in an indictment of Chinese technology giant Huawei, a report said on January 16.
The Wall Street Journal, citing anonymous sources, said the Justice Department is looking into allegations of theft of trade secrets from Huawei's US business partners, including a T-Mobile robotic device used to test smartphones.
The Justice Department declined to comment on the report and Huawei did not respond to a request for comment.
The move would further escalate tensions between the US and China after the arrest last year in Canada of Huawei's chief financial officer Meng Wanzhou, who is the daughter of the company founder.
The case of Meng, under house arrest awaiting proceedings, has inflamed US-China and Canada-China relations.
Two Canadians have been detained in China since Meng's arrest and a third has been sentenced to death on drug trafficking charges -- moves observers see as attempts by Beijing to pressure Ottawa over her case.
Huawei, the second-largest global smartphone maker and biggest producer of telecommunications equipment, has for years been under scrutiny in the US over purported links to the Chinese government.
Huawei's reclusive founder Ren Zhengfei, in a rare media interview on January 15, forcefully denied accusations that his firm engaged in espionage on behalf of the Chinese government.
The tensions come amid a backdrop of President Donald Trump's efforts to get more manufacturing on US soil and slap hefty tariffs on Chinese goods for what he claims are unfair trade practices by Beijing.
In a related move, lawmakers introduced a bill to ban the export of American parts and components to Chinese telecom companies that are in violation of US export control or sanctions laws -- with Huawei and fellow Chinese firm ZTE the likely targets.
"Huawei is effectively an intelligence-gathering arm of the Chinese Communist Party whose founder and CEO was an engineer for the People's Liberation Army," said Republican Senator Tom Cotton, one of the bill's sponsors.
Democratic Senator Chris Van Hollen said in the same statement: "Huawei and ZTE are two sides of the same coin. Both companies have repeatedly violated US laws, represent a significant risk to American national security interests and need to be held accountable."
Last year, Trump reached a deal with ZTE that eases tough financial penalties on the firm for helping Iran and North Korea evade American sanctions.
Trump said his decision in May to spare ZTE came following an appeal by Chinese President Xi Jinping to help save Chinese jobs.