A reactor at Slovenia's only nuclear power plant was being shut down Wednesday after a water leak, but there was no danger to people or the environment, the country's nuclear watchdog said.

A statement from the Nuclear Safety Administration said the reactor at the Krsko power plant was being shut down as a precaution so that technicians can inspect the cause of the problem.

"There has been no impact on the environment and none is expected" following the Wednesday afternoon leak, the statement said. "The event did not affect employees, the nearby population or the environment."

The European Union's executive body said Slovene authorities had reported a problem with the plant's primary cooling system.

"A loss of coolant has occurred in the primary cooling system," said the statement from the European Commission.

The information was immediately passed on to all 27 EU nations and an emergency team at the EU's energy directorate was placed on alert.

The Krsko nuclear power plant in southwestern Slovenia has been in operation for about 20 years, according to its Web site. The facility generates about 5 billion kilowatts of electricity a year, or roughly 40 percent of Slovenia's energy needs, its operators said.