Huawei worked with another Chinese company, Panda International Information Technology, on several projects in the region over eight years, as suggested by work orders, contracts and spreadsheets published by the Washington Post.

The Post points out that if Huawei gear contains US technology, then it could have been ignoring international sanctions and providing a back door method for the North Koreans to get US tech.

The documents were passed to the newspaper by a former employee of the company who believed they were in the public interest, and they were supported by other documents provided by two others. The Washington Post says that Huawei would neither verify of denying the authenticity of the documents, which don't indicate the company's specific involvement in the North Korea projects.

"Huawei is fully committed to complying with all applicable laws and regulations in the countries and regions where we operate, including all export control and sanction laws and regulations of the United Nations, United States and European Union", said a spokesman for the company in a statement.