Chinese equipment vendor ZTE plans to appeal a decision by the US Department of Commerce to impose export restrictions for allegedly violating export controls on Iran.

The restrictions, which went into effect on 9 March, require ZTE suppliers worldwide to apply for an export licence before shipping any US-made equipment or parts to ZTE. The applications generally would be denied, the Department said.

A source familiar with the matter told Reuters that ZTE plans to appeal after its lobbying efforts failed to curb the restrictions. The Chinese company has spent $5.1 million over the last four years in an attempt to appease national security concerns, Reuters said.

ZTE and the Department of Commerce are having discussions, which an official told Reuters have been constructive.

The company previously said in a statement that it has been working with relevant US government departments on the investigations, maintaining constant communication with relevant departments, and is committed to fully addressing and resolving any concerns.

The Chinese government last week expressed its “dissatisfaction” after the US slapped ZTE with sanctions for having allegedly sold telecoms gear to Iran.

Its component suppliers in the US also face significant losses due to the export restrictions. Shares of its optical component suppliers fell sharply after the sanctions were announced.