Former Samajwadi party leader Amar Singh on Wednesday faced intense grilling from the supreme court as he sought to drop his allegations against Congress and its chief Sonia Gandhi in connection with the tapping of his phone in 2006.

Singh informed a bench of justices G S Singhvi and A K Ganguly that he was dropping the allegations he had made against Gandhi in his petition in the phone tapping case.

He was represented by senior advocate Abhishek Manu Singhvi, who is also a Congress spokesperson.

"In view of your revised affidavit how do you affirm the allegations against the political party through its president," the bench said, adding, "Your averment which is based on personal knowledge cannot change."

Singh had filed the petition in 2006.

"When you say that its personal knowledge, it means it is something that you know personally and which cannot change with the passage of time," the court observed when Singhvi submitted that he had made the allegations in 2006 out of his personal knowledge that political rivals including Congress party was behind the tapping of his phone.

"If that is your personal knowledge, it cannot be contradicted by yourself," the court said, noting, "Your personal knowledge is dubious and the court is a victim of your affidavit."

While pulling up Singh for changing his stand, the bench said, "The court started hearing your case. Many years have passed and many hours were devoted in your case on the basis of your averments. We tend to rely on them."

Singhvi was visibly uncomfortable when the bench repeatedly asked him to read out the portion of his petition in which Singh had made allegations against the Congress party and its president.

During the hearing, the court said, "In the petition, you have said that the party in power was misusing the authority but now everything is found to be bogus."

The court also asked as to why the petition should be entertained.

"Why should the court entertain the petition about a person who has not come with clean hands?," the bench asked.