SEMICONDUCTOR Manufacturing International Corp. (SMIC), the largest chipmaker on the Chinese mainland, said its U.S. suppliers have been issued with letters telling them they are subject to additional export restrictions.

SMIC is evaluating the impact of the U.S. Bureau of Industry and Security’s export restrictions, which could have “material adverse effects” on its production and operations, it said in a statement Monday, confirming earlier reports of the controls.

The chipmaker has had “preliminary exchanges” with the U.S. Bureau of Industry and Security (BIS) in relation to the export restrictions and will continue to actively facilitate communications with relevant U.S. government departments.

SMIC also said it has been operating in compliance with the relevant laws and regulations of all jurisdictions where it performs its businesses.

The company also advised shareholders and potential investors “to exercise caution when dealing in the securities of the company.”

In September, Reuters reported that the BIS had issued letters informing certain companies they must henceforth obtain a license before continuing to supply goods and services to SMIC.

The letters stated that exports to SMIC “may pose an unacceptable risk of diversion to a military end use” to China.

Such measures recalled those imposed by the U.S. Department of Commerce on Huawei Technologies Co., the Shenzhen-based maker of smartphones and networking equipment.

At the time of the reports, SMIC said it had not received any notice from the Department of Commerce regarding the reported restrictions and said it had no relationship with China’s military.

SMIC is the largest semiconductor foundry on the Chinese mainland, though it trails behind Taiwan Semiconductor Manufacturing Co., the global market leader. Both companies rely heavily on equipment from companies based in the United States or U.S.-allied countries to produce chips for clients.

Earlier this year, SMIC raised US$6.6 billion in a listing in China’s tech-centric STAR Market, aiming to use the cash to kickstart manufacturing into more advanced technology. (SD-Agencies)