By Pete Harrison
LUXEMBOURG, June 5 (Reuters) - A water leak at Slovenia's Krsko nuclear plant threatened to overshadow European Union environment talks on Thursday, as Slovenia reassured there was no danger and fended off criticism of its handling of the case.
The accident at the plant tripped the EU's "Ecurie" early warning system on Wednesday afternoon, but some member states were initially informed that the incident was a drill.
"It was a mistake ... a genuine human error," Environment Minister Janez Podobnik told reporters via a translator outside the Luxembourg meeting of environment ministers.
"The nuclear safety agency has already apologised it used the wrong form," he added. "It used the form that had exercise (written) on it. There was no need for any protective measures for people and the environment. And only a very minor repair is needed."
But non-nuclear neighbour Austria said such confusion should not happen.
"It must be immediately clarified and I will ask for that in the council," said Austrian Environment Minister Josef Proelle. "Why were the directly affected neighbours confronted with a test announcement? This should not happen."
Environment group Greenpeace said the incident highlighted the danger of a nuclear resurgence within Europe to help reduce CO2 emissions.
"Those who are planning to build more nuclear reactors must head this warning and reject nuclear technology," said Greenpeace nuclear campaigner Jan Beranek.
The International Atomic Energy Agency in Vienna said the incident was not serious, as to its knowledge there had been no radiation leak.
"The Slovenian authority has four levels of incidence and this was levelled as level one, which they say was an 'unusual incidence'," said IAEA spokesman Ayhan Evrensel.
Italian Environment Minister Stefania Prestigiacomo played down the situation, saying there had been too much "over-alarmism".
Germany also showed confidence in Slovenia's handling of the situation.
"It's positive, because it shows that the system works," said German Environment Minister Sigmar Gabriel. "I favour that somebody triggers an alarm unnecessarily than it is set off one time too little."
Ministers were meeting in Luxembourg to discuss the EU's efforts to combat climate change, including an ambitious target to cut CO2 emissions by one fifth by 2020, compared to 1990 levels.
(Additional reporting by Ilona Wissenbach, Ingrid Melander)