CANBERRA -- Chinese telecommunications company Huawei still hasn't been told exactly why it was banned by the Australian government from taking part in the build-out of high-speed national broadband network, Huawei Australia chairman John Lord told a parliamentary committee here Friday.

"With the NBN decision, I was summoned to the attorney-general's at short notice and we were advised of the decision that Huawei would not be participating in the NBN," he told the joint intelligence and security committee of inquiry into potential reforms of National Security Legislation hearing from Huawei Technologies.

"We were disappointed we were not given a chance to answer any concerns that may have led to that decision," he said, adding "The actual reasons that we were not included in the NBN we do not know".

Huawei is the world's largest manufacturer of telecommunications equipment, ahead of Swedish firm Ericsson. Its Australian office opened in 2004 and is the hub for its business across Australia, New Zealand and the South Pacific.

Last year, the Labor government banned the company from tendering for work on the $37.4 billion NBN project citing unspecified security concerns, apparently based on advice from security agencies.