Tatas who stand to benefit from such a move having dual technology ironically is supportive of the COAI stand. Tatas have bagged pan-India GSM licence, and are now member of COAI also besides being member of the CDMA operators association AUSPI.

"If internal number portability is allowed between two networks of one operator, it will make audit of spectrum usage impossible, therefore, there could be manipulation in the payment of spectrum charges resulting in huge loss to the government," COAI Director General T V Ramachandran said in a presentation to the Department of Telecom.

COAI also fears that such a policy would lead to manipulation of subscriber figures to get additional spectrum.

Allowing operators to set up their own database, then the concept of a separate MNP licensee becomes redundant, there by government loses entry fee of Rs 1 crore that would have been paid by each licensee. Government would also set to lose annual licence fees paid by MNP licensee at one per cent of the revenue.