The Central Board of Direct Taxes has asked a committee to probe commercial transactions mentioned in some of the tapped conversations of corporate lobbyist Niira Radia.

The committee headed by a Director-General in charge of Investigation, Delhi, will probe a transaction between Tata Realty and Infrastructure Ltd (TRIL), a Tata group firm, and real estate firm Unitech, in 2007, among others, finance ministry sources said.

TRIL had extending what it describes as a commercial advance of Rs 1,600 crore to Unitech in 2007. Vaishnavi Corporate Communications owner Niira Radia is heard discussing what appears to be a Tata-Unitech Deal in one of the several phone conversations tapped by CBDT.

Radia complains that Unitech owed the Tatas Rs 250 crore and that its cheques bounced, in a conversation with former prime minister Atal Bihari Vajpayees foster son-in-law Ranjan Bhattacharya.

The government is investigating if Unitech used the money to pay for the telecom licence it was awarded in early 2008. Unitech paid the Department of Telecom Rs 1,651 crore in January, 2008, for the 2G licence. It did not have any experience in the telecom sector and was a real estate firm then.

In October, 2008, Unitech formed Uninor, a joint venture with Norwegian teleco Telenor. It paid Rs 6,200 crore for new shares in Uninor. In a statement to ET the company defended the transaction: Unitech has not sold any shares held by it in Uninor to the Telenor Group.

The Telenor Group has invested Rs 6,135 crore in fresh shares over four rounds of investments, linked to milestones, to hold 67.25% stake in the venture. While the licences were issued in February 2008, the first round of investment from Telenor in Uninor was received after 13 months, in March 2009, and the fourth round in February 2010 after receiving FIPB clearance.

Over the past 4 months, our JV with the Telenor Group, Uninor, has consistently added over 2 million new subscribers each month, emerging as the 2nd or 3rd largest operator in terms of subscriber additions pan India and the number 1 in many circles, the statement said.

The TRIL-Unitech deal is just one of the transaction covered by the DG (Investigation) probe. Finance ministry sources said there were many such conversations with a commercial angle, which will be investigated by the CBDT panel. Since CBDT did not have the wherewithal to go through the transcripts of the tapes it sought the help of CBI. CBI is examining the transcripts.

In its affidavit submitted to the Supreme Court last month, CBI had said: About 3,500 calls have now been analysed and the process is ongoing. The recordings, which (are) the main basis of the investigation regarding her role, are still being examined.

It is examining 5,851 calls 3,500 were analysed till then and transcripts running into 82,665 pages. The exercise is prolonged and is continuing as 5,851 calls recordings, many of them being 30-40 minutes long, have to be listened (to) and analysed, CBI had said in its affidavit.