The accusations were made by friends of Mr Hamilton after it emerged yesterday that the allegations which forced him out of office concerned two financial interests which he had properly registered when he was a backbencher.
Ministerial sources privately admitted that the allegations put to Mr Hamilton on Tuesday by Richard Ryder, the Chief Whip, were intended to force his resignation. 'He was handed the pearl-handled revolver and refused to use it,' one Cabinet source said.
The new allegations concerned interests in Mobil Oil and Plateau Mining - already declared in the register of members' interests, and his indirect links to a third company had been investigated by the Serious Fraud Office.
The Prime Minister told MPs it was the discovery of new allegations which had convinced him that Mr Hamilton could not continue as a minister, but ministers said privately the intention was to force Mr Hamilton's resignation.
Ministers believe Mr Major decided that Mr Hamilton had to go after reading a statement issued in Mr Hamilton's Tatton constituency without the MP's authority. It compared his fight to clear his name to Mr Major's libel action over Scallywag magazine's allegations of an affair. His friends believe the Government was paying back old scores against Mr Hamilton, an anti-European. Ministers flatly deny this.
Mr Hamilton is considering making a personal statement to the Commons as the first step to clearing his name of allegations of 'sleaze', friends said last night.
With Mr Major facing Prime Minister's Questions, the former minister for corporate affairs at the Department of Trade has told friends he will not make a statement today.
But Mr Hamilton's friends said he could still use his right to make a personal statement on his resignation to MPs.
Mr Hamilton has privately told his supporters he wants to clear his name.
'He does not want revenge . . . He feels very hurt by the whole affair,' said one close friend.
Ministers privately said Mr Hamilton could, from the backbenches, inflict serious damage on the Government.
In an exchange of letters, published in later editions of the Independent, Mr Hamilton disclosed his bitterness at being forced to resign after receiving the Prime Minister's support last week. Mr Hamilton wrote to Mr Major: 'You confirmed the allegations of impropriety made against me are unsubstantiated and I thank you for that.
'However, you announced also that the combined effect of the allegations disabled me from carrying out my responsibilities as minister for corporate affairs and that you had no alternative but to ask for my resignation. I think it is sad and deeply disturbing that I have been forced to leave office because of foully motivated rumour and a media witch-hunt.'
In his reply, Mr Major said the inquiry by Sir Robin Butler, the Cabinet Secretary, had found that the allegations against Mr Hamilton were unsubstantiated.
'However, I must be concerned at the general perception of the Government and capacity of ministers to carry out their work without damaging distractions.
'I believe that the cumulative impact of the allegations that you face - even though I accept that they are unsubstantiated - did make it impossible for you to continue to carry out your responsibilities.'
Inside Parliament, page 9 Letters, page 19 (Photograph omitted)