Polish Prime Minister Donald Tusk said authorities believe an object that crashed in eastern Poland overnight was a Russian Kh-101 cruise missile, although experts are continuing to examine the site before making a final determination.

Speaking during an emergency meeting, Tusk said all available evidence points to the missile being Russian, but officials want complete certainty before drawing definitive conclusions.

"All the indications are that it was a Russian Kh-101 cruise missile, but we want to be 100% certain about the type of missile and who launched it," Tusk said.

The object came down near the village of Tarnawa-Kolonia in Lublin Voivodeship during Russia's large-scale overnight missile and drone attack on Ukraine.

According to Tusk, Poland's armed forces were prepared to intercept the missile if it had continued deeper into the country's airspace.