India feels that Pakistan will not "come clean" on the evidence provided on the Mumbai attacks as it will involve exposing the nexus between its Inter Services Intelligence and terror groups.

While continuing to build world pressure against Pakistan, New Delhi [Images] is also preparing a list of Pakistan-based terrorists and terror groups involved in attacks in India and are planning to approach the United Nations Committee on Terrorism [Images] to seek a ban on them.

The list will include Jaish-e-Mohammad chief Masood Azhar and those behind various terror attacks in India like the serial train blasts in Mumbai in July 2006.

"We have not received any information from Pakistani authorities through the proper channels. Whatever we are hearing like you is through the media. This is not the way a government can respond," External Affairs Minister Pranab Mukherjee [Images] told mediapersons.

"We expect them to investigate and let us know the outcome of that investigation. Till now we have not received any information from Pakistan," Mukherjee said.

Dubbing Pakistan's response so far as "totally unacceptable", official sources said if such an approach continues, Islamabad will lose even the "shred of credibility" it has.

Making it clear that New Delhi cannot let perpetrators of the Mumbai carnage go scot-free, the sources said India is keeping its options on dealing with Pakistan open, but refused to spell them out.