But Mr Whelan said it was clear there were people briefing against ministers.
Charlie Whelan, ex-adviser to Chancellor Gordon Brown, stoked the row by insisting that government aides do feed stories to the media which are unfavourable to ministers.
And former prime minister Baroness Thatcher warned against the growing use of spin doctors in government.
Announcing that she was to write a new book on leadership, she said: "In this age of spin doctors and soundbites, the ever-present danger is that leaders will follow fashion and not their instincts and beliefs."
The row over Labour spin erupted at the weekend when novelist and former party fundraiser Ken Follett attacked media briefings against individual ministers.
He said Tony Blair should end the "backbiting" by government insiders.
His claims have been denied by cabinet minister Mo Mowlam and by the prime minister's official spokesman Alastair Campbell - one of the chief targets of Mr Follett's attack.
But Mr Whelan said it was clear there were people briefing against ministers.
The spinner-turned-political commentator said there were "a lot of flunkeys" at Labour headquarters and Number 10, though he declined to name names.
"It's ridiculous to claim this doesn't go on and what they should be saying is 'This has got to stop' rather than saying it doesn't happen, because it clearly does."
Blair's role?
Veteran Labour MP Tony Benn also joined the attacks, accusing the prime minister of running Britain "like some medieval monarchy", surrounded by courtiers and determined at all costs to hang on to power.
Earlier, former armed forces minister Doug Henderson said: "The spinning that everyone knows has been taking place, as journalists will tell you, against certain cabinet members should stop.
"It is very damaging to the party and, I believe, to the government."
He said the issue was "is the prime minister behind the detail of the briefings or is it a bit of private enterprise by his political advisers?"
"If the prime minister is behind it, he should think again and look towards cabinet government and have more confidence in the cabinet."
Mr Follett had said the prime minister was "totally responsible" for the briefing of journalists by senior officials - and said their actions were damaging the party.
'Over the top'
The government launched a vicious attack on Mr Follett after his comments.
And Cabinet Office Minister Mo Mowlam said the idea she was the target of secret briefings was "rubbish".
Mr Campbell said "there is not a shred evidence" for Mr Follett's claims.
"He says that I poisoned journalists against Mo and other ministers. Not true."
Mr Campbell said: "I have a golden rule in speaking to journalists: I never say anything bad about anyone in this government."
Labour MP Fraser Kemp said all governments had publicity machines - the Tories had had Bernard Ingham, for example.
And speaking to newspapers was not a bad thing, he said.
He denied the prime minister was involved in "spinning" against cabinet members.