The Dutch government is preparing for a potential nuclear disaster and is stocking up on iodine pills to protect people against radioactivity in case of accidents, according to reports.

A total 15 million iodine pills have been purchased by the government to be given to people living within 100 km radius of any nuclear plant, reports the Daily Mail.

The move comes as concerns arise over ageing reactors across the border in Belgium. Neighbouring Germany had pressed Belgium to shutter two ageing nuclear power plants near their border due to concerns over their safety.

The Dutch announcement came a day after Belgium said it planned to distribute iodine pills to its entire population of 11 million as part of a revised nuclear emergency plan, a measure unveiled just months after police discovered that Islamic State (ISIS)-linked bombers were working to breach Belgium's nuclear security, reports NBC News.

Belgian security services learnt in February that two men had been spying on one of the country's senior nuclear scientists. There were also reports that ISIS plans to build a "dirty bomb."

Although Belgium has yet to finalise how to distribute the pills, Dutch health ministry spokesperson Edith Schippers said the Dutch would "follow" how (the Belgians) carry out the distribution of the pills and where they will be available—whether people will have to go and find them at a pharmacy or at a local health service clinic.

She said the pills will be initially given to children under 18 and pregnant women living within a 62-mile radius of a plant.

The rest of the supply of 15 million pills could be made available to everyone caught up in a potential accident, including tourists, visitors and workers or even to people living in border areas near Germany's Emsland plant and the two Belgian facilities, Doel and Tihange, said Schippers.

Iodine pills help to block radiation absorption from the thyroid, according to experts.

The Netherlands has one nuclear power plant—at Borssele in the southwest. Belgium, on the other hand, has a handful of nuclear facilities with a total of seven reactors. The first commercial nuclear reactor went online in 1972, according to Eurowire.