Labour MP Brian Sedgemore said a leaked letter from the Secretary of State for Transport, Sir George Young, showed a clear intention to deny compensation to people whose homes had been blighted by the long-running rail-link saga.
The letter reveals a proposal to exert political pressure on the all- party select committee that considered the rail link legislation.
The Independent has learnt that the letter was the subject of embarrassing, closed-door exchanges between MPs on the select committee in October last year.
The committee was warned that a formal complaint of Contempt of Parliament would be made against Sir George, for consideration by the Speaker, unless he provided guarantees that he would not attempt to "nobble" the committee.
He provided that assurance, and the matter was dropped.
But Mr Sedgemore said last night: "This is a contempt of Parliament, and an attempted fraud on the thousands of residents who live on or near the planned route of the line.
"That contempt lies at the heart of government because no fewer than six cabinet ministers were involved - the circulation list even included Michael Heseltine, Tony Newton, Leader of the House, and Chief Whip Alastair Goodlad.
"I always regarded the prime mover of the dirt, Sir George, as a perfect gent and a decent bloke, but that only shows that when a system turns rotten, everyone is dragged down and sucked in to bad ways."
In the letter, Sir George reported to William Waldegrave, Chief Secretary to the Treasury, that select committee recommendations delivered in July last year had added an estimated pounds 150m to the cost of the pounds 3bn rail-link scheme.
However, he then added there was little ministers could do about that. "The select committee sits in a quasi-judicial capacity," Sir George said. "Where it has reached decisions or made recommendations which go to the protection of private affected interests, these carry special weight; we could not set them aside lightly."
But Sir George said that the committee was due to meet again on 17 October 1995, when it would start to consider potentially expensive recommendations on noise, property purchase and compensation for victims living near the proposed route.
He told Mr Waldegrave that in those circumstances, it would be "prudent" for himself and John Watts, the railways minister, to intervene.
The plan was to "indicate" to the Tory chairman of the committee, Sir Anthony Durant, and his Tory deputy, Irvine Patnick, "that it would not take much more than the costs already added by the committee to tip the Channel tunnel rail link project towards non-viability".
"If they want to see the project go ahead they should not be tempted to play to the gallery over noise, property-purchase and compensation in October.
"Kind words are due for Sir Anthony's handling of the committee, but not for the indulgence of the committee's decisions north of the Thames," he said. And in a clear reference to the political pressure faced by the Tories, he added: "Our supporters in Kent cannot be too happy."
Sir Anthony was in Paris and unavailable for comment yesterday. Mr Patnick did not return The Independent's call.