The United States is urging Americans in Belarus to leave the country “immediately,” citing spillover risks from the war in Ukraine, including a buildup of Russian troops in Belarus.

Belarusian President Alexander Lukashenko threatened to use nuclear weapons, deployed to his country by Moscow, if “aggression is launched against us.” This comes as neighboring NATO states have deployed thousands of troops near the Belarusian border amid heightened tensions between Minsk and Warsaw.

Polish Defense Minister Mariusz Blaszczak said Thursday that Warsaw plans to deploy 10,000 troops to its border with Belarus as part of a buildup that began after Wagner fighters traveled to Belarus.

Poland on Tuesday said it was rushing more troops to its border with Belarus after accusing Minsk of violating its airspace with military helicopters, a claim Belarusian officials denied.

A group of Belarusian exiles is receiving training in Poland to prepare for a day when they return to Belarus to take on the government of President Alexander Lukashenko, The Times reported on Sunday.

Deputy Chief of the General Staff of the Armed Forces of Belarus, Ruslan Kosygin, said Belarusian forces will strike primarily at Poland's infrastructure.

Poland's Defence Minister tweeted on Friday that British engineering troops have started a reconnaissance on establishing cooperation with Polish soldiers in strengthening the fence on the Polish-Belarusian border.