Sir George Young, whose committee investigated the case against Mr Conway, said it had turned the spotlight onto the "complaints machinery" and numbers were soaring.

His comments, in an interview for BBC Radio 4's The Week in Westminster, raise the prospect of more MPs having their financial affairs investigated, although he stressed it was not yet clear if any of the complaints have "substance".

"People have read the Conway report and a lot of constituents have remembered some long-lost grievance about a member of Parliament and a lot of complaints are now coming in," Sir George said.

These went first to the Parliamentary Commissioner for Standards, John Lyon, he advised, adding: "I think it's fair to say he's going to be quite busy over the next few weeks, sifting these complaints.

"We will have to see how many have substance. But certainly the Conway affair has raised the profile of the MPs' complaints machinery."

Sir George continued: "I do think we have a job to do now to restore the reputation of the House of Commons as a whole and we must respond to this challenge - post Conway - that we can put our House in order."

Commons speaker Michael Martin has announced a "root-and-branch" inquiry into all aspects of MPs' expenses, after Conservative MP Mr Conway was suspended over payments to his son.

It is not expected to report back to the House of Commons until MPs return from the summer recess in October.

The Prime Minister has already ordered Labour MPs to declare any family members who they pay from parliamentary allowances, while Conservative leader David Cameron has told frontbench Tories to do the same and urged backbenchers to follow suit.