His comments came after BJP president Nitin Gadkari demanded resignation of Singh and Chidambaram stating that what Raja had said in court showed that the top leadership of the government was aware of all 2G transactions.
Raja told a Delhi court hearing the 2G case that Chidambaram, then Finance Minister, had told the Prime Minister that dilution of shares by 2G licencees to attract FDI did not not amount to sale of licence.
Sibal told a press conference it was "unfortunate" that President of a national political party like BJP demanded resignation on the basis of arguments made by Raja in the court. "He (Gadkari) should have consulted Arun Jaitley (senior BJP leader) or some other lawyer".
On the allegations that two new telecom licencees -- Unitech and Swan-- divested their equity at premium, the Telecom Minister asserted that "there was no disinvestment and it was only dilution of stake by bringing in additional equity".
Asked whether the Prime Minister knew about the dilution of equity by Unitech and Swan, Sibal said "yes, the Prime Minister knew that it was dilution of equity" by way of issuing new shares and there was no divestment of promoters'' equity.
He also took a dig at BJP for not acting against Karnataka Chief Minister B Yeddyruppa who is facing allegations of corruption.
"The way these issues are being raised by them (BJP) ahead of Parliament session, it seems thay have no other issue and they are adopting these tactics to disrupt the session", Sibal said.