Senior officials in the agency confirmed that CBI would look into the FIPB approval given to the Aircel Maxis deal in which allegations of coercion and bribery have surfaced, resulting in a probe.
The agency's move to investigate the issue of FIPB clearance will take the probe to the doors of Finance Ministry which has so far been limited to Telecom Ministry.
The sources said agency will soon be filing its first charge sheet in the matter and the issue of alleged fraudulent approval of FIPB, if substantiated, will be part of subsequent charge sheets which could be filed at the later stage.
CBI in 2011 had filed FIR in the case alleging that Dayanidhi Maran, the then telecom minister had used his influence to help Malaysian business tycoon T Ananda Krishnan acquire Aircel by coercing its owner C Sivasankaran.
It was alleged by Sivasankaran that the then telecom minister had favoured Malaysia-based Maxis group in the takeover of his company and in return investments were made by the company through Astro network in a company owned by the Maran family.