Marco Rubio (Photo: EPA)

Secretary of State of the United States Marco Rubio said that the intrusion of Russian drones into Polish airspace is unacceptable, but "it remains unclear" whether Russia deliberately sent them to Polish territory. He told reporters before his trip to Israel and the United Kingdom, transmits Reuters.

Rubio noted that the United States considers the incident with Russian drones in Poland "an unacceptable, unfortunate and dangerous development."

"There is no doubt that the drones were launched intentionally. The question is whether the drones were aimed specifically at Poland," he added.

Rubio said that if the drones were targeting Poland, "if the evidence leads us to that conclusion, then obviously that would be a step leading to a serious escalation."

"There are a number of other possibilities, but I think we'd like to get all the facts and consult with our allies before we draw any conclusions," the Secretary of State said.