A 35-year old nuclear plant in Slovenia automatically shut down because of a water supply problem, its operator said Thursday, ruling out any radiation danger.

"The shutdown procedure was triggered because of anomalies in a valve regulating the water supply system," the Krsko nuclear plant said in a statement.

The incident comes three months after a shutdown for regular maintenance work.

The 700-megawatt Westinghouse reactor in Krsko was built in the former Yugoslavia and went into service in 1983. It is located in Slovenia, but has been jointly run with neighbouring Croatia since the breakup of Yugoslavia.

It was originally due to be shut down in 2023, but two years ago Ljubljana and Zagreb decided to extend its lifetime by another 20 years.

The new incident comes nearly a decade after a cooling water leak at the plant which triggered a Europe-wide alert procedure, the first since the Chernobyl catastrophe in 1986.

Several NGOs, including Greenpeace, have demanded the dismantling of the station which is just 25 kilometres (16 miles) from Zagreb, because of its age and also because of earthquake risks in the region.

Krsko covers around 20 percent of Slovenia's electricity needs and 15 percent of those in Croatia.

bk-phs/jh/ser

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