Poland says it is working towards the 'complete isolation' of Belarus after it accused the country of carrying out military provocations on its border, including an incursion by two helicopters on Tuesday.
The Nato country deployed “additional forces and resources, including combat helicopters” to its border following the incident, and summoned Belarus' charge d'affaires to provide an explanation.
The Polish military initially denied any border violation had occurred but later, after consultations, said the intrusion took place “at a very low height, hard to intercept by radar”.
Residents of areas near the eastern Polish city of Bialowieza, close to the Belarus border, shared accounts on social media of what they said were border violations before the defence minister issued its statement.
The growing presence of Wagner mercenaries has sparked alarm in Warsaw in recent weeks, with the Polish Prime Minister describing the situation on the border as 'increasingly dangerous'.
On Wednesday, a top Polish official said his government will look to 'isolate' Belarus and punish its President Alexander Lukashenko for his increasingly threatening posture.
“I am convinced that in co-operation with Lithuania and Latvia we should lead to the complete isolation of Belarus in the future,” Deputy Interior Minister Maciej Wasik told public television in an interview on Wednesday. “Lukashenko reacts only to force.”
The Belarusian military denied any such violation by its helicopters and accused Poland, one of Ukraine's most fervent backers in its conflict with Russia, of making up the accusation to justify a build-up of its troops.
Belarus' Defence Ministry, writing on Telegram, said Warsaw had changed its mind about the incident “apparently after consulting its overseas masters”.
“This statement was not backed up by data from Poland,” it said. “The Belarusian Defence Ministry views it in the manner of an 'old wives' tale' and notes there were no border violations by Mi-8 and Mi-24 helicopters.”
Earlier on Tuesday, Mr Lukashenko mockingly told Poland it should thank him for keeping in check Wagner mercenaries now stationed in Belarus after a failed mutiny against the Kremlin last month.
Mr Lukashenko joked at a meeting with Putin last month that some of the fighters were keen to press into Poland and “go on a trip to Warsaw and Rzeszow”. Rzeszow is a city near the Polish-Ukrainian border.
Poland recently closed its border over infiltration fears after observing 100 Wagner fighters had moved closer to the Belarusian city of Grodno near the Polish border.
However, the Institute for the Study of War has said Wagner fighters in Belarus pose no military threat to Poland unless they are re-equipped with mechanised equipment.
Belarus has allowed Russian President Vladimir Putin to use its territory as a launch pad for the Ukraine invasion, but Mr Lukashenko has not committed his own troops to the war.
The ex-Soviet state has a long history of animosity with Poland, as does Russia.
State news agency Belta quoted him on Tuesday as saying that the Poles “should pray that we're holding on to (the Wagner fighters) and providing for them. Otherwise, without us, they would have seeped through and smashed up Rzeszow and Warsaw in no small way. So they shouldn't reproach me, they should say thank you.”