Action against Telecom Minister A Raja - who belongs to ally DMK and has been dogged by graft accusations - is the prerogative of the prime minister, the Congress said on Tuesday even as it moved against Ashok Chavan and Suresh Kalmadi over corruption allegations.

Congress spokesperson Jayanthi Natarajan told reporters outside parliament that the party cannot comment on allegations of Raja's involvement in the 2G spectrum scam as the matter is subjudice.