An Iranian partner of Huawei Technologies allegedly tried to sell embargoed American antenna equipment to another Iranian firm.
The buyer pulled out of the deal when it learnt the items were subject to sanctions and before any equipment was delivered.
Documents seen by Reuters show that Soda Gostar Persian Vista, a Tehran-based supplier of Huawei equipment in Iran, tried to sell to MTN Irancell 36 tower antennas made by Andrew for €14,364 a pop.
The gear was supposed to be delivered in Tehran on February 3, 2012, to "Huawei warehouse ready for installation".
Huawei had an agreement with CommScope, which owns Andrew, to buy Andrew antennas and other equipment and use the products in Huawei systems.
The Andrew antennas were part of a Huawei telecommunications order that MTN Irancell had placed through Soda Gostar.
The US has banned the sale of its technology to Iran for years and the evidence will be seen as proof that Huawei is a rogue company. Huawei insists that it complies with US law and requires Soda Gostar "to follow applicable laws and regulations".
The US House Intelligence Committee slammed the company for failing "to provide evidence to support its claims that it complies with all international sanctions or U.S. export laws".
South Africa's MTN Group, which owns 49 percent of MTN Irancell, said the Iranian telecoms firm wanted 36 German-made antennas which were not subject to sanctions. For some reason Huawei, through its local partner Soda Gostar, gave it US manufactured antennas by mistake.
It was identified as an error and as a result the tender request was cancelled with Huawei and the German goods obtained from a local reseller, Paul Norman, MTN Group's corporate affairs officer, said in a statement.
He said that the whole incident proved that there were strong processes in place in MTN and Irancell to ensure compliance with US sanctions.
In a statement, Vic Guyang, a Huawei spokesman, acknowledged that MTN Irancell had cancelled the order.
But he pointed out that Huawei did not participate in the delivery of this project because Huawei has been and continues to be in strict compliance with all relevant international and local laws and regulations.
There is some concern in the US that China has become a backdoor for Iran to obtain embargoed US computer equipment. In March and April, ZTE was caught selling millions of dollars worth of gear to Iran.