As the row over allegations by Llew Smith exploded into an angry exchange of letters between William Hague and the Prime Minister, a member of the committee suggested Tony Blair should look to his laurels.
Peter Bottomley, a former Tory minister, said if Mr Smith complained to the committee as he had threatened to do, it should take the matter seriously.
"Assuming Mr Smith is right, someone else has got it wrong and that could be due to ignorance, apathy or aggression. All that can be put right by saying we were wrong, you were right and we are sorry," he said.
Last night 20 Conservative MPs signed a Commons motion demanding that the privileges committee should investigate the claims by Mr Smith, a long-time opponent of devolution.
Downing Street tried to close down the issue last night as William Hague, the Conservative leader, tried equally hard to keep it alive.
Mr Blair has flatly denied that Ron Davies, the Secretary of State for Wales, told the MP for Blaenau Gwent he would be thrown out of the Parliamentary Labour Party.
In a letter to Mr Hague, who raised the issue in Parliament on Wednesday, Mr Blair said: "As I told you yesterday I investigated the allegations ... I am satisfied with the result. I now consider the matter closed."
Mr Hague will raise the issue again in a speech tonight to Scottish Tories in Perth. In his reply to Mr Blair last night he said Ron Davies' special adviser, Hugh Roberts, had breached Civil Service rules when he spoke to Mr Smith's local council leader about the subject.
"The issues here go way beyond internal squabbles in the Labour Party. Far more important is the question mark which now stands against the willingness of ministers to admit the truth," he wrote.Reuse content