According to reporting in Reuters, German authorities made the announcement on 13 July. The 62-km fence is part of some 240km of barriers put up along the frontier by German states earlier in 2020 after ASF was detected in wild boar only 15km away from the German border.

“As ASF continues to come closer to Germany, Mecklenburg-Vorpommern (state) has been intensively preparing for months to prevent the worst-case happening,” state Agriculture Minister Till Backhaus said. “The fence to protect against wild animals along the border is another part of our prevention measures.”

Poland had been consulted about the fence extension and it was agreed to build at least five metres from the actual frontier inside German territory, he said.

The pig disease, which has hit the world's top pork producer China hard, originated in Africa before spreading to Europe and Asia. It has killed hundreds of million of pigs, while reshaping global meat and feed markets.

Germany had feared a spread of the disease after cases were confirmed in wild boars in western Poland in recent months with one Polish case found in January only 12 km from the German border.

Cases have also been recently confirmed in about 10 other European countries in wild boars that are believed to be spreading the disease.

ASF is not dangerous to humans but fatal to pigs. Some countries impose import bans from regions where ASF has been discovered in wild boars, while major slaughtering programmes of farm pigs may also be needed to eradicate the disease.