The plan for a "temporary storage" of waste from the Krsko nuclear plant, which is jointly owned by Croatia and Slovenia, has been an open issue for several years.

The protest comes ahead of a Monday meeting about the location of the dump site between EU members Croatia and Slovenia.

The demonstrators, including many high-school students and local politicians, gathered in Novi Grad and marched towards a bridge over the Una river which forms the natural border between Bosnia and Croatia.

"We don't want nuclear waste hundreds of metres from the Una river, which is a natural jewel, near our homes, our pastures, our apiaries," Srebrenka Golic, a top environmental official and leading critic, told the crowd.

"Croatia knows very well this, they are ignoring us... but we will not allow them to poison our people," she added.

Zagreb's plan would see the waste disposed of at a former army barracks in Cerkezovac on Croatia's side of the border.

Another option would be to put the dump site in Slovenia, closer to the plant.

Bosnia says the disposal of the nuclear waste at Cerkezovac would endanger the 250,000 to 300,000 people living in the area, notably on the banks of Una.

They also fear the site would not be temporary.

"It can become a large European landfill for nuclear waste of European countries which do not know what to do with it," Golic said.

The Krsko plant, which began full operation in 1984, was built by Croatia and Slovenia when they were both part of the former Yugoslavia alongside Bosnia and other former republics.