"I don’t love it. I don’t like when that happens," Trump told reporters.
"This could be big trouble. I’ll let you know later," he added, saying he expected to be briefed on the situation later.
Estonia said three Russian MiG-31 jets crossed around 9 km into its airspace on Friday morning and stayed for about 12 minutes before being forced out by NATO aircraft.
Tallinn called the breach "unprecedentedly brazen," and said it would request consultations under Article 4 of the alliance’s founding treaty.
Russia’s Defence Ministry denied any violation, saying the planes flew over neutral waters of the Baltic Sea en route to Kaliningrad.
NATO said the incursion was "yet another example of reckless Russian behaviour," while Estonia summoned Moscow’s top envoy in Tallinn to lodge a formal protest.
The incident came three days after Russia and Belarus concluded their "Zapad-2025" joint military exercises, which included drills simulating the use of nuclear weapons.
Trump’s administration has been under scrutiny over its muted response to earlier Russian drone incursions into Poland this month.
Separately, Poland said on Friday two Russian fighter jets violated the safety zone of the Petrobaltic drilling platform in the Baltic Sea.
(ał)
Source: IAR, PAP, Reuters