New Delhi, March 2: The Aircel-Maxis deal that has embroiled Congress leader P. Chidambaram and his son Karti was discussed in the Lok Sabha today in spite of protests and walkouts by the Opposition for taking up a matter that was sub judice.

In his reply after the debate, finance minister Arun Jaitley didn't name either but told the House investigations were on and "nobody, however important, would be spared".

The discussion and the walkouts came after AIADMK MPs had yesterday stalled proceedings demanding action against both father and son for their alleged involvement in the deal.

The Congress alleged a "match-fixing" between the BJP and the Biju Janata Dal as a BJD leader had moved a notice demanding the discussion. The Opposition also protested Speaker Sumitra Mahajan's decision to allow a debate on a matter that was before a court and when the motion of thanks to the President's February 23 joint address was still being discussed.

"The sanctity of the President's address is being flouted," a Congress MP alleged.

But the Speaker justified her decision, saying she had received a notice from BJD leader Bhartruhari Mahtab to hold a discussion on the deal. The Congress and the Left walked out a little while after the debate started.

Maxis is a Malaysian company owned by business tycoon T. Ananda Krishnan, a Malaysian citizen of Sri Lankan Tamil origin. Aircel was first promoted by NRI tycoon C. Sivasankaran. In 2006, Maxis took over Aircel by acquiring 74 per cent shares.

The deal became controversial after the 2G scam when the Supreme Court asked the CBI to probe then telecom minister A. Raja's predecessors. Chidambaram, a former finance minister, was sucked into the controversy following allegations that he misused his position to help Karti benefit from the 2006 deal.

The Trinamul Congress stayed back in the House but accused the Speaker of giving preference to an "unimportant" deal. "Which issue is more important? We wanted the House to complete the debate over the President's address. The Aircel-Maxis deal issue has come out in only one newspaper and people are saying that it needs to be verified," Trinamul leader Sudip Bandyopadhyay said before the party's MPs also walked out.

Yesterday, the AIADMK MPs had waved copies of an English daily claiming the Enforcement Directorate had unearthed evidence against Karti and Chidambaram.

Mahtab, who initiated the discussion, said: "We are trying to expose the match-fixing between the Congress and the BJP."

"The investigation team has got all the details. But, I would ask the government, why no FIR has been lodged?" he said. "Are Congress and BJP doing a match-fixing here?"

Jaitley denied the allegations of going slow. "We have no holy cows to protect," he said, adding the CBI had filed a chargesheet in one case.

The Rajya Sabha is scheduled to discuss the issue tomorrow.