Poland on Tuesday said it was taking action to stop the spread of African swine fever as it confirmed its first two cases and the European Union worked to end a Russian ban on its lucrative pork exports.

A buffer zone has been set up along parts of the eastern border with Belarus, Lithuania -- where the disease is present -- and Ukraine, Poland's chief veterinary officer Janusz Zwiazek told reporters in Warsaw.

Officials have ordered farmers to fence in their land, lay down disinfectant mats and test and monitor shipments of live pigs out of the zone.

African swine fever is harmless to humans but lethal to pigs and has no known cure, posing a grave threat to commercial pig farms.

Moscow banned pork imports from the EU on January 29, after Lithuania confirmed the disease in two wild boars. Brussels slammed the move as "disproportionate" and is now in talks with Moscow on the matter.

Russia absorbs a quarter of the bloc's pork exports, worth around 1.4 billion euros ($1.9 billion) annually.

Poland is one of the EU's leading pork exporters with exports in 2013 valued at 912 million euros ($1.2 billion).

State veterinarians confirmed the disease in Poland following tests on the carcasses of wild boar found near the village of Szudzialowo, just under a kilometre (mile) from the border with Belarus.

Lithuania ordered a mass cull of wild boars, saying it would shoot 90 percent of the estimated 60,000 animals living on its territory to halt the spread of the disease.

Zwiazek said Tuesday Poland was "not planning a mass depopulation of boars in the affected areas because that would just open up territory for possibly infected animals coming over the border" from Belarus or Lithuania.

"Poland has up to 252,000 wild boar (not counting the newborns) and we routinely shoot up to that number each year to manage the population," he said, explaining that stocks of the highly fertile animals could double within a year without large-scale annual hunts.

African swine fever has spread throughout the Balkans, the Caucasus and Russia since 2007, and is endemic to areas of Africa, according to the United Nations' Food and Agriculture Organisation (FAO).

The FAO warns of "vast losses" if it migrates from Russia to China, which is home to half of the world's pigs.