"Congress remained aloof from this matter to save the government. They should have come forward and said nothing is wrong," Raja said in an interview to WION on Thursday.
Raja was the telecom minister in the Congress-led UPA government from May 2007 to November 2009. He resigned in 2010 after the then Comptroller and Auditor General (CAG) Vionod Rai indicted the minister for not distributing the 2G spectrum in a transparent manner leading to a loss of Rs 1.76 lakh crore to the exchequer.
Raja hit back at the former CAG. "Vinod Rai is a blatant liar. They wanted to train their guns only at me. No one came to hear my side of the story," the DMK leader said.
Explaining how he was acquitted in the 2G scam, Raja said the investigators could not corroborate the evidence. "Whatever you accuse me of, you have to present evidence for that. But all the documents were in my favour, the investigators couldn't prove anything so I was acquitted," Raja said.
He also said that members of former Prime Minister Manmohan Singh's Cabinet were not true to him. "Those who failed in court wanted to use the Prime Minister's Office (PMO). He didn't even know about spectrum availability. Dr Singh remained silence because of the Supreme Court and media," Raja said.
"There were variations within the Cabinet regarding 2G. Nobody in the government defended the policy of the government. Cut-off date was not Raja's brainchild. It was the brainchild of then secretary and officers. In fact I was against the cut-off date," he added.
The CBI, during the course of its investigation, had alleged that the decision to advance cut-off date for accepting the applications for grant of 2G spectrum licences was taken to "favour" Unitech - a charge which was never accepted by Raja.
The DMK leader also said that he will seek a ticket for 2019 Lok Sabha elections. "I will always be part of politics," Raja said.
Raja was also grateful to his party chief M Karunandhi. "Karunanidhi came to jail to console me."
Last month, Raja and 16 other accused in the 2G scam were acquitted of corruption charges by the special CBI court. Judge OP Saini pronounced his verdict as "not guilty" for all accused due to lack of evidence. The judge noted that the prosecution has "miserably failed to prove any charge."
"I place the 2G verdict on your feet with gratitude. I'm waiting to hear your words," Raja said in the letter. He also alleged that the spectrum attack has tainted the DMK's ideological movement and questioned, "Who will punish those who tainted your 80 year public life?"
Reiterating that his actions brought a "revolution" in the telecom sector, Raja further said in the letter that as a minister in the UPA government, which was in power at the Centre when the spectrum scam happened, he gave 59 crore mobile connections against the 60 crore target set before 2012. "A shame that even UPA govt couldn't realise it was trapped in the plot to bring it down," Raja said in his letter.