The Conservative co-chairman, Grant Schapps, has cast doubt on reports in two newspapers that a senior Tory aide described party activists as "mad, swivel-eyed loons".
Asked who was behind the alleged comments, he told Channel 4:
Unfortunately I can't reveal the answer to that, simply because I was not there and as far as we are aware it was not even said, but we just don't know.
I don't believe anyone senior would say this type of thing, it's not an attitude or a view I have ever heard expressed in No 10, in Central Office. We respect and work with people who work incredibly hard as volunteers, unpaid, for the party.
I'm trying to make clear, I don't believe it's ever been said. You can always run a story that said there were 250 people in a room and one of them said this.
The trouble is with this story we don't know who is supposed to have said it.
Conservative Party Chairman Grant Shapps described Lord Feldman as being "absolutely straight and true to his word" following allegations that a senior aide described grassroot party activists as "mad, swivel-eyed loons".
Conservative party co-chairman Grant Shapps conducted a guided tour of parliament for three internet business associates under the name Michael Green when he was a Tory backbencher, a Guardian investigation has revealed.
The report claims that one of the men kept a blog - which has since been deleted - that read:"I was given an exclusive night-time tour, amidst high level security, at ... the Houses of Parliament. Accompanied by 3 top Internet marketers. With no one else present. Apart from a watching policeman."
Mr Shapps, who bought the internet entrepreneurs dinner in a Commons restaurant on the same evening in 2006, denied last month that he was "living a double life".
A Conservative Party spokesman has denied the claims, and said:
"This is complete rubbish. Grant held a dinner for three friends who knew him personally. There is absolutely nothing improper about this."