The center was assigned the task of assessing the potential threat posed by Huawei, which supplies equipment to mobile phone companies in Belgium (Brussels), Orange Belgium and Telnet. The Center reports directly to the Prime Minister.
"So far there have been no technical indications ... of a threat of espionage," an IAEA spokesman said on Monday. "This is not a final report on this issue, but we will continue to examine it."
Huawei is facing a campaign by Washington, which has prevented it from developing fifth-generation communications networks because of concerns over its links with the Chinese government. Washington says the rest of the West must ban Huawei's technology.
Last month, Germany imposed tougher standards on all telecom providers without specifically referring to Huawei.
But Britain has publicly criticized Huawei for failing to bridge long-standing security holes in mobile network devices and revealed other "technical problems".