Mobile companies had suggested that number portability must be first implemented in fixed line services since 95 per cent of landline subscribers are with the incumbent operator Bharat Sanchar Nigam.
Trai, however, had said that implementing number portability in fixed lines is not feasible right now.
It is not clear yet whether there would be a change in this stance after DoT completes its discussions with the operators.
Mobile number portability has already been implemented in places like Hong Kong, the UK, Australia, the US, Germany, France, Netherlands and Singapore.
Even Pakistan, which has mobile penetration of a mere 6.9 per cent, is planning to introduce number portability.