A US congressional investigation of a year has concluded that Chinese telecom companies including Huawei and ZTE pose a security threat to the country and should be barred from contracts and acquisitions in the country.

A draft report prepared by the House Intelligence Committee said that two companies cannot be trusted to be without the influence of Chinese authorities and they can be used to undermine US security. The investigation was launched after concerns were raised that the Chinese authorities might use these companies for economic or military espionage or even cyber attacks.

"Based on available classified and unclassified information, Huawei and ZTE cannot be trusted to be free of foreign state influence and thus pose a security threat to the United States and to our systems," a part of the draft report says.

Huawei and ZTE have both said that they do not have any ties with the Chinese governments. Senior executives from the companies, who appeared for a hearing before the panel, said that the companies are focused on conducting business and not politics. The committee noted that the two companies did not provide satisfactory answers about their relationship with the Chinese government.