"This is a perverse report and fraud report and cannot be considered to be JPC report," CPI leader Gurudas Dasgupta said outside Parliament along with BJP leader Yashwant Sinha.
Both parties were also highly critical of Speaker Meira Kumar's ruling disallowing any debate on the issue at the presentation stage during Zero Hour.
The report, which gave a clean chit to Prime Minister Manmohan Singh in the 2G spectrum scam saying he was "misled" by the then Telecom Minister A Raja, was tabled in the Lok Sabha by JPC Chairman P C Chacko amid pandemonium.
Dasgupta said, "The report is a fraud as it does not take into account the role of finance minister and others. It has only found that one villain that is Raja. PM knew what is happening despite that JPC did not take it into account."
Asked whether CPI has joined hands with BJP, Dasgupta said, "We are all members of JPC and no party is untouchable on the floor of Parliament."
BJP said it was "unprecedented" the way it was tabled in the House and voiced unhappiness with the Speaker's conduct.
"It was unprecedented. The manner in which the report was finalised was in violation of rules and norms of the House," Sinha said.
He said the "Speaker did not allow us to raise points of order. MPs have rights to raise points of order under specific rules but she overruled it."
Sinha said, "We did not want the fabricated JPC report. Despite our protest the Speaker remained unmoved. It is very very saddening. Because it is a commentary on the way and the manner in which our parliament is functioning.
"It is a very sad day for our parliamentary democracy and we strongly protest what has happened in the House."
Dasgupta too was critical of Speaker's actions.
"I have never commented on the behaviour of the Chairman or the Speaker. Today I am saying that I disapprove the way Speaker Meira Kumar turned down our notices. We did not rise accidentally as notice was given in the morning for it.
"Despite that, our legal notices given on time, we are not allowed to make our submission. She could have overruled us after listening to us."
Senior BJP leader Murli Manohar Joshi also criticised the way the JPC report was tabled in the House.
"...It is a travesty of rules of conduct of Parliamentary proceedings. I think this is a bad precedent," he said.
Joshi said certain MPs, who were also members of JPC, were raising important points of order but they were not heard.
"They were not given chance to speak and place their point of view. The Speaker was at liberty to disallow them. But to not allow them to even present their point of view, it's a very bad precedent," he said.
JPC report on 2G tabled in LS amid din, DMK walks out
Chhattisgarh: Mahendra Karma's wife fights to redeem chequered legacy
Ashok Gehlot speaks: 'Vasundhara was second fiddle, used Modi well'
Babri Masjid demolition... 'I was there'
For some Union ministers, Rajasthan's crushing defeat is personal