"These are not calm times," Piotr Müller said in an interview with state broadcaster TVP 1.
"It must be underlined that we are under real threat, both in terms of the migration flows orchestrated by" Belarus' President Alexander Lukashenko, "but also because of upcoming Russian-Belarusian military exercises, which pose a real danger," he added.
Müller told TVP 1 that Poland was prepared for a scenario where the situation could "heat up, with some apparently accidental events potentially taking place at the Polish, Lithuanian or Latvian border" during the Zapad 2021 maneuvres.
"We saw what happened in Crimea, Georgia and eastern Ukraine," Müller said.
"Right now, Russian-Belarusian military exercises are set to begin on the Polish border any moment, and we also have information that migrants from Arabic countries have been brought to Belarus for weeks," he added.
"These are around 10,000 people who may cross into Poland, Latvia or Lithuania at any minute," he also said.
Together with Lithuania, Latvia and Estonia, Poland has accused Belarus of organising an influx of immigrants into its territory as a form of "hybrid warfare."
A group of such migrants has been camped outside the Polish border for the past three weeks, with Belarusian officials positioned behind them.
The migrants have sought to enter Poland, but border guards, policemen and soldiers are warding them off. A strip of land along the boundary has also been fenced off on the Polish side.
EU Commissioner for Home Affairs Ylva Johansson has said the standoff between Poland and Belarus "is not a migration issue, but part of the aggression" of Belarusian strongman Alexander Lukashenko "toward Poland, Lithuania and Latvia, with the aim to destabilize" the European Union.