Department of Education and Skills bosses have been accused of acting like bullies themselves over their treatment of the award-winning charity Bullying Online.
Bullying Online has refused to sign up to the government's Anti-Bullying Alliance (ABA).
It claims the £570,000 project, which includes a tsar scheme, will be a huge waste of money which will ultimately be used to boost the coffers of local authorities for whom some of the tsars work.
The controversy stems from the charity's refusal to agree to a code of conduct preventing them speaking out about the activities of the government-funded ABA.
A clause in the code of conduct states members should "not speak, write or brief against the Alliance or other member organisation".
It means the Harrogate-based charity, which last year helped more than 8,000 people and offers support to up to four suicidal schoolchildren a day, will not have access to the ABA.
Under the initiative, which was launched by the Government in July, each tsar or regional co-ordinator will identify and build on existing anti-bullying strategies in their region.
Their roles will include creating regional networks linking with other groups such as education advisers, youth organisations, health workers and parent support services.
Liz Carnell, director of Bullying Online, said: "We cannot have any input into the Anti-Bullying Alliance because we refuse to sign a code of conduct which breaches our European human rights, prevents us questioning the ABA's actions publicly and stops us exercising our democratic right to contact MPs with our concerns.
"The ABA wants to gag this charity because it doesn't like us telling the public we think the tsar scheme is a waste of money and that we don't think private firms should be on its advisory group when no teachers' or parents' organisations are represented.
"We think the behaviour of this government-funded organisation is scandalous.
"We have always said we will speak up for children and parents and see no reason why a Government-backed scheme should need secrecy."
The group's fears were echoed in Parliament this week when Liberal Democrat education spokesman Phil Willis accused Schools Minister Stephen Twigg of imposing a 'gagging order' on Bullying Online.
Mr Willis said that overall his party supports the government's attempts to tackle bullying.
But he added: "Bullying Online, an organisation which has been very much at the vanguard for nearly a decade in terms of dealing with bullying in schools and is the most respected group within the country, is being denied access to the Alliance simply because it will not sign a code of conduct which says it must not criticise government officials.
"Surely that is unacceptable. There should not be a gagging order on any organisation, certainly not a well-respected organisation like Bullying Online.
"That's bullying."
Mr Twigg said he would look into the matter and revealed that he had already received "a considerable number of letters" from MPs about it.
He said the Government had introduced the ABA along with an "anti-bullying charter...which has been endorsed by all the professional associations and by the key voluntary sector organisations and children's charities".
"We believe the recent anti-bullying week and the work of the Alliance is very critical in providing a real concerted drive to give support and confidence to those facing bullying in our schools," he added.
Bullying Online is calling for a public inquiry to investigate the running of the Anti-Bullying Alliance.
Since it was formed in 1999, Bullying Online has been contacted by thousands of parents and children at its website, www.bullying.co.uk.
The award-winning charity is calling for answers to find out:
? Whether any government ministers or DfES officials are behind the attempt to gag the charity.
? Why the nine anti-bullying tsar jobs were not advertised openly but went to ABA members.
? Why some schools didn't receive anti-bullying packs in time for Anti-Bullying Week.
? Why the ABA failed to launch its new website in Anti-Bullying Week.
? Who is getting £100,000, which is supposed to help the parents of bullied children.
? Why Bullying Online. which does innovative and effective work helping children and parents. cannot get a penny from the ABA's £570,000 budget.
? Why organisations like the Family Planning Association and private firms are part of the ABA.
ABA spokeswoman Tracy Sands said: "The code of conduct is not designed to be a gagging order. The ABA is made up of 50 organisations who act pretty much as a co-operative.
"The code is there to enable them to move forward in a professional manner with each other.
"We would never suggest that anyone should not speak out about any issues to do with bullying."
tony.gardner@ypn.co.uk