The European Commission has backtracked on its declaration this week that the Government can exempt schools from paying water charges, which leave some facing bills of €10,000 a year.
On Wednesday, the commission said it could "see no reason" why schools could not be exempted because this would not threaten the EU water conservation legislation.
The declaration put pressure on the Minister for Education and Science Mary Hanafin because TDs are already coming under pressure from parents who are facing having to fundraise to pay the charges.
The commission's original declaration, made verbally to The Irish Times and by e-mail to Green Party TD Paul Gogarty, prompted a flurry of contacts between the Department of the Environment and Brussels.
In one e-mail, seen by The Irish Times last night, the Department of the Environment complained that the commission's remarks were "seriously misleading",.
Ireland secured a derogation under the water framework directive so that it did not have to impose water rates on home-owners. The "Irish understanding", said department official Tom Corcoran, had always been that it could not exclude anything that was not exempt before the EU conservation rules were agreed in 2000.
Mr Corcoran asked if the commission was now saying that this "is no longer a binding condition and "that it is therefore open to a member state to grant new exemptions to any categories of water users".
If so, then, Mr Corcoran asked, if the commission could clarify whether the cost of extending an exemption could be met by the State or would it "have to borne" by other water users.
"We are already in receipt of a Letter of Formal Notice in relation to our implementation of the Water Framework Directive, so you will appreciate that we wish to avoid the risk of further infringement proceedings should we proceed to apply new exemptions from application of the polluter-pays principle in the case of water charges.
"Accordingly, we need confirmation that the introduction of any new exemption (to schools in the first instance) will not place Ireland in breach of Article 9 of the Water Framework Directive," he asked pointedly.
Replying, commission official, Peter Gammeltoft said pre-2000 "established practices" were "a very important element to consider in implementation as it confines the application of this provision to existing situations".
Meanwhile, an organisation representing primary school principals last night said that a survey of 153 schools shows that they are facing an average bill next year €3,300 - and that 84 of them cannot afford to pay the charges.
