The government on Thursday said it has asked state-owned telecom firm BSNL to conduct security audit of its network amid security concerns raised over equipment supplied by Chinese vendor Huawei, Parliament was informed.

"The government has issued instructions to BSNL for security audit to the effect that networks and its elements are free from any malwares and are not susceptible to remote hacking, irrespective of origin of manufacturing, before operationalisation," Minister of State for Communications and IT Gurudas Kamat told the Rajya Sabha in a written reply.

The minister was answering a query on measures taken by the government to ensure proper testing and security audit of telecom network and equipment supplied by Chinese vendor Huawei, being installed in South India.

To another query on 3G spectrum, Kamat accepted that there is a disparity between the availability of 3G spectrum across different circles. To address this, the government has signed an agreement with the defence ministry, he added.

Under the agreement, the ministry of defence would release 3G spectrum in a phased manner in a span of three years from the time of signing the MoU.

Defence would be provided alternate optical fibre cable network to vacate the spectrum, he added.