The move comes amid fears that African swine fever – which has been found in two dead wild boars in Belgium – could threaten the billion-dollar Danish pig industry.

The Scandinavian country produces about 28 million pigs a year – an industry worth 30bn Danish kroner ($4.6bn) – and exports almost $1.7bn in pork products.

If there were an outbreak of the disease, “exports to non-EU countries would have to shut down”, the government said.

Jakob Ellemann-Jensen, the Danish minister for the environment and food, said the government would “do everything we can to prevent African swine fever reaching Denmark. And now we can finally get started on erecting our wild boar fence.”

Such an outbreak happened in Lithuania in 2014, where thousands of animals have been killed.

Denmark is also easing hunting restrictions and stepping up fines for livestock transport that has not been properly disinfected.

The fence, expected to be completed by the autumn of this year, will stretch for nearly 70 kilometres and will be electrified.

African swine fever, which can be lethal for animals but not humans, has not yet been spotted in Denmark or Germany but is common in eastern Europe.