Finance Minister Pranab Mukherjee has refused to comment on the raging controversy over his ministry's note to the Prime Minister's office on the 2G-scam. Contending it is sub judice, the minister, while addressing mediapersons at New York, evaded questions suggesting a rift between him and Home Minister P Chidambaram, whom he called as his 'valued' colleague. Pranab was talking to media after he met Prime Minister Manmohan Singh and briefed him about the issue.