India on Monday promised to respond to any information sought by Pakistan in connection with the probe into the terror attack on Mumbai but underlined that the request should come through official channels only.

External Affairs Minister Pranab Mukherjee said India will cooperate 'as and when' necessary but ruled out a joint investigation into the attacks.

"Whatever information we get from Pakistan, we will respond to it. But information must be made available through official channels and not through media," he told reporters in New Delhi.

He said India is ready to cooperate with Pakistan 'as and when it is necessary' in its investigation into the Mumbai attacks and in this direction referred to the material provided to Islamabad about linkages in that country.

"As far as the joint investigation is concerned, I have told you we are havingour own investigation," he said.

After being provided the dossier of evidence on Mumbai attacks, Pakistan has sought more information and in this regard given a list of 30 questions. India has said it is examining it and will provide whatever information is possible.