"Numerous drones entered Polish airspace overnight and were met with Polish and NATO air defences. The NATO Secretary General is in touch with Polish leadership and NATO is consulting closely with Poland," spokeswoman Allison Hart wrote on X.

NATO's top commander in Europe, US General Alexus Grynkewich, said the alliance reacted "quickly and decisively to the situation".

A spokesman said in a statement the incident was the "first time NATO aircrafts have engaged potential threats in allied airspace".

The statement said fighters from the Netherlands' air force had responded and engaged the potential threats.

German Patriot air defence systems in Poland were placed on alert and an Italian early warning aircraft was launched.

"NATO... is committed to defending every kilometre of NATO territory, including our airspace," the statement said.