The Semiconductor Industry Association (SIA) claimed Huawei had worked to bypass widening US trade sanctions by secretly building chip manufacturing capabilities, with an estimated $30 billion in funding from the governments in Beijing and Shenzhen, Bloomberg reported.

Huawei’s undisclosed production facilities include at least two existing factories and at least three more under construction, the news agency wrote.

The US-headquartered SIA told Bloomberg Huawei hid its involvement by registering the plants under other companies’ names, meaning the vendor could be violating US sanctions by indirectly buying chipmaking equipment and related supplies.

Samsung, Taiwan Semiconductor Manufacturing Co, Intel and ASML are among the SIA’s members.

In a statement to Bloomberg, the US Department of Commerce’s Bureau of Industry and Security said it is unsurprising Huawei and other Chinese companies had sought state backing to develop domestic technologies and it is keeping an eye on the situation.

Earlier in the year, Huawei founder Ren Zhengfei outlined the company’s development of local alternatives to components it cannot source from US companies, noting it redesigned more than 4,000 circuit boards and replaced more than 13,000 components from across its product range.

The US began targeting Huawei in 2019, imposing various restrictions.

Subsequent constraints target exports of advanced chipmaking equipment to China from Japan and the Netherlands, alongside an ongoing political campaign encouraging many countries to ban China-made 5G network equipment.