New Delhi, Aug. 24 -- The CBI is likely to confront all the six signatories on the Foreign Investment Promotion Board (FIPB) file relating to alleged irregular clearance of FDI to the tune of Rs 300 crore by INX Media with former Finance Minister P Chidambaram who is currently undergoing custodial interrogation by CBI in the case.

The agency is also mulling whether to take Chidambaram to Mumbai to confront him with approver in the case Indrani Mukherjea or bring her here for confrontation with the former Finance Minister.

In view of the high profile nature and vast experience of Chidambaram as a lawyer, the investigators are grilling him under direct supervision of agency director RK Shukla, sources said.

Chidambaram has so far been deny...