The 88-year-old leader said he had told the PB he could only stand by the truth in the matter and not by the official line of the party that it was a fabricated case.
Achuthanandan was referring to his removal from the CPI(M)'s apex body when he was Chief Minister in the context of charges brought against Vijayan pertaining to a contract awarded to Canadian company SNC Lavalin to renovate three power stations in Kerala, when the latter was electricity minister in 1997.
"I was dropped from the PB for telling the truth that the deal with SNC Lavalin involved irregularity...It was the finding of the CAG...This was not a case framed to harm anybody," Achuthanandan, now leader of the opposition in the state, told Malayalam channel Mathrubhumi News.
"I told them (when the issue came up for discussion in the PB) that I could only stand by truth... I was dropped from the PB, to which I have been a member for over 24 years", Achuthanandan, a founder leader of the CPI(M), said.
"How could Vijayan become an accused in the case if there was nothing irregular in the case...The contention in the CBI report that he has not made any monetary advantage is supported only by the statement of a witness," he said.
The case pertains to an agreement with SNC Lavalin which allegedly caused a loss of Rs 374.50 crore to the exchequer. The final agreement with the company was signed when Vijayan was power minister in the 1990s in the LDF ministry headed by the late E K Nayanar.
The case has been investigated by the CBI and the trial is on in the CBI court here.