A Raja, former telecom minister and key accused in the 2G case, on Thursday started his defence in a Delhi court by grilling his one-time close aide who had recorded his statement against him with the CBI.

Raja, who had protested that he will not cross-examine the witnesses until CBI files its third charge sheet and makes a statement that its probe in the case was complete, threw questions to Aseervatham Achary ranging from his conversation with corporate lobbyist Niira Radia to frequently changing his residence and mobile numbers.

With the third charge sheet already filed on December 12, Raja, who had also said that he will cross-examine the witnesses only when public servants depose on the issue of government policy, asked Achary if Radia was "instrumental" in procuring a 'benami' Tata Motors Agency for him.

This was however, denied by Achary who said the conversation was regarding his intention to join politics.

"It is incorrect to suggest that I have a benami Tata Motors Agency in Tiruchirapalli. I am not aware if she (Radia) was warning me about this. It is incorrect to suggest that she was instrumental in procuring this agency for me," Achary answered to the question put forth by Raja's counsel Sushil Kumar.

Achary told the court that he had conveyed to Raja about his intention to join politics in 2008 on which Raja suggested him against the same.

"I expressed my desire for the first time to A Raja of my joining politics in July 2008. On this, A Raja told me that politics is not an easy field. I gave a thought to the given by Raja about politics. Thereafter, I decided not to enter politics and I gave highest regard to the advice of A Raja," Achary said.

Kumar asked Achary, former additional private secretary to Raja, about his residences, questioning as to how could he afford the rent of houses in the prime locations in the national capital and whether one of the these was owned by his mother-in-law.

Achary told the court that his mother-in-law had died long back and the house in Delhi was a rented accommodation.

"It is incorrect to suggest that Dwarka flat was purchased in the name of my mother-in-law on the basis of power of attorney," he said.

Kumar also asked questions regarding employment of his wife and if Achary took Raja's help in getting a job for her, which was denied by the witness.

"It is incorrect to suggest that my placement with A Raja facilitated her (Achary's wife) employment in the aforesaid company (Hindustan Latex). It is incorrect to suggest that I used the name of A Raja with the MD of the aforesaid public sector company for seeking employment for my wife," he said.

Achary also told the court that Raja's reluctance to relieve him from his job became a reason of developing a "difference" between them.

During his cross examination, Achary told the court that earlier his name was M Aseervatham which he changed to Aseervatham Achary in 2003 as he got attached to Hinduism and changed his religion from Christianity.

Raja also left no opportunity to question Achary about the frequent change in his mobile number.