Pressure continued to mount on the Conservative leadership over claims an ally of David Cameron described grassroots activists as "mad, swivel-eyed loons" who forced Tory MPs to adopt hardline stances on divisive issues.
Party co-chairman Lord Feldman was forced strenuously to deny making the alleged comments after rumours swirled on the internet that he was responsible, and Downing Street also insisted no one at Number 10 had made the remarks.
Grant Shapps, who shares the party chairman role with Lord Feldman, questioned the accuracy of the potentially incendiary remark reported in a number of papers, claiming: "I don't believe it's ever been said."
In an effort to avoid a damaging rift with Tory volunteers, a party spokesman said the prime minister had the "highest regard" for the Conservative Party's activists and praised their "incredibly hard work".
Newspaper reports claimed Tory MPs were under pressure from their local parties to take a stand on issues such as Europe.
The ally of the prime minister reportedly said: "There's really no problem. The MPs just have to do it because the associations tell them to, and the associations are all mad swivel-eyed loons."
The comments were made by a figure with "strong social connections" to the prime minister, The Times and Daily Telegraph reported.
But Shapps disputed the papers' version of events, setting the party's high command on collision course with the press.
He compared the row to the "plebgate" stories surrounding former chief whip Andrew Mitchell and internet rumours against peer Lord McAlpine which have resulted in libel claims.
Asked who was behind the "swivel-eyed loons" remark at a Conservative Friends of Pakistan event, Shapps told Channel 4 News: "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."
He added: "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."
After the story appeared speculation about the origin of the comments began on the internet and quickly led to Lord Feldman's name being raised as the potential source.
But in a statement Lord Feldman, a friend of Cameron's from their days at Oxford, said: "This is completely untrue. I would like to make it quite clear that I did not nor have ever described our associations in this way or in any similar manner. Nor do these alleged comments represent my view of our activists."
Lord Feldman, who is taking legal advice on the matter, added that he was "very disappointed by the behaviour of the journalists involved, who have allowed rumour and innuendo to take hold by not putting these allegations to me before publication".
Number 10 said the Prime Minister "supports Lord Feldman's position" and it was "categorically untrue that anyone in Downing Street made the comments".
A Tory spokesman said: "The prime minister, like every member of the Cabinet, has the highest regard for the Conservative Party's activists - for their patriotism, their dedication, their incredible hard work at elections and between elections and the time they give of their own free will to the Conservative cause."
Relations between the party leadership and grassroots traditionalists have been strained by Cameron's support for gay marriage, the coalition with the Liberal Democrats and the perennially difficult issue of Europe.
Tory MP Brian Binley said if the remarks were made it would not be a surprise because the leadership has a "disdainful" view of the party's volunteers.
Binley, a member of the party board which is chaired by Lord Feldman, said: "I certainly will be wanting to know more about it when we have our next board meeting."
He said: "Certainly the gap between the party leadership and the party's voluntary sector in the country is sizeable. I have made that complaint again and again."
Binley added: "If this was said, by whoever, it would not surprise me. There has been a disdainful view of the voluntary party."
Former Tory Cabinet minister John Redwood told BBC1's Andrew Marr Show said if anyone made the comments they should be disciplined.
"If there is such a person, not named of course, they should be reprimanded because I, and my colleagues, think our members are very good people who work hard for our local communities they serve as councillors," he said.
"We agree with their views on Europe, we think that the European government is not working in Britain's interest, it is taxing us too much, it is costing us too much and we want that new relationship."
Conservative vice-chairman Bob Neill attacked the press over the "swivel-eyed loons" story.
He told Sky News' Murnaghan programme that Lord Feldman had "denied very explicitly that he said it" and added: "I think we have to be very, very wary of this, I think, rather slipshod bit of journalism where neither he nor Downing Street were ever approached for comment."
Neill said he had never heard Lord Feldman "or anyone in central office or in Downing Street say anything of that kind".