According to the Wall Street Journal (WSJ) report, Sprint Nextel is blocking China's Huawei Technologies and ZTE from a multi-billion-dollar network upgrading contract largely due to national security concerns, about Chinese vendors, in Washington.

Going by the WSJ's Friday report, the Pentagon and some US lawmakers have expressed apprehensions about the ties between the two Chinese telecommunications-equipment makers and the Chinese government and military.

Citing "people familiar with the matter," the WSJ report said that the Defense Department and lawmakers are concerned about the security implications of allowing equipment manufactures by Huawei and ZTE into the decisive US infrastructure.

Raising the issue of potential dangers pertaining to the deployment of Huawei and ZTE's equipment by US carriers, a group of four US lawmakers said in a letter to the FCC last month that the two companies could be subject to "significant influence by the Chinese military which may create an opportunity for manipulation of switches, routers, or software embedded in American telecommunications network so that communications can be disrupted, intercepted, tampered with, or purposely misrouted."

Despite the fact that Huawei and ZTE have denied any links with the Chinese military and have strongly objected to their cataloging to the contrary, the WSJ report said that Alcatel-Lucent and Samsung are the two finalists for Sprint's network modernization contract.