Countries on NATO’s eastern flank have warned of new dangers linked to Russia as elements of the Wagner mercenary group prepare to arrive in Belarus.

Latvia’s prime minister, Krisjanis Karins, said the presence of Wagner in neighboring Belarus posed an urgent threat of "infiltration” into the European Union and called on the bloc to intensify security measures.

His warning came a day after Poland said it would bolster security on its frontier with Belarus amid fears that the presence of the forces may intensify what it calls hybrid warfare with its eastern neighbor. Prime Minister Mateusz Morawiecki was preparing to present a Polish plan to boost security on the EU’s eastern fringe in Brussels on Thursday.