Parliament''s Public Accounts Committee has summoned corporate lobbyist Niira Radia and Tata Group Chairperson Ratan Tata on April 4 to discuss their role in the 2-G Spectrum allocation case.

Sources said the PAC will meet on April 4 and 5 to discuss the 2-G spectrum allocation case which had led to the resignation of Telecom Minister A Raja. He was later arrested and is still in custody.

This comes after the editors of two news weeklies appeared before Parliament's Public Accounts Committee on March 14 in connection with the alleged 2G spectrum allocation scam as panel member N K Singh, whose conversations figure in the Radia tapes, recused himself from the proceedings.

The PAC recorded evidence of Vinod Mehta and Manu Joseph, Editors 'Outlook and 'Open Magazine' respectively, which carried transcripts of the phone conversations corporate lobbyist Niira Radia had with others. The recordings had exposed among other things the efforts made by Radia, who represented top corporate clients, to get DMK leader A Raja the job of Telecom Minister after the UPA won the Lok Sabha elections in May 2009.