The Parliamentary Standing Committee on Coal and Steel, headed by Trinamool Congress leader Kalyan Banerjee, named three top officials who joined private firms after retirement.
The officials named by the Committee are former Power Secretary R V Shahi -- an independent director of Jindal Steel and Power, former Chief Secretary of Jharkhand P P Sharma joining Abhijeet Group and former Coal India Chairman N C Jha joining Monnet Energy and Ispat.
But, it expressed anguish over no inquiry being conducted on the issue by the Coal Ministry in past.
"The Committee fail to understand as to why no inquiry has been conducted so far to expose the unholy nexus between such bureaucrats and coal companies who have been alloted captive coal blocks," said the Committee report tabled in Parliament.
It also said that the officers in the ministries and PSUs "directly or indirectly connected with the allotment of coal blocks joining the private mining companies after their retirement raises serious doubts about their being impartial when they were associated with the process of allotment of coal blocks".