BRUSSELS 

Bulgaria is not carrying out an investigation into the disruption of the GPS of the plane carrying European Commission President Ursula von der Leyen, said the nation’s premier on Tuesday, stressing that the incident is not considered a hybrid or cyber threat.

Speaking to journalists, including public broadcaster BNT, Rosen Zhelyazkov said: “Part of the methods of waging modern wars include the so-called radio-electronic warfare, which is interference in the radio frequency spectrum, and this has been observed in recent years in war zones.”

He added: “This interference is not targeted at one or another aviation object. Such things happen daily."

Bulgaria's air traffic management acted according to protocol, he said.

The incident took place during von der Leyen's visit to Bulgaria on Sunday, with an EU Commission spokesperson saying later they are "well aware that threats and intimidation are a regular component of Russia's hostile actions."

But Kremlin spokesman Dmitry Peskov on Monday denied any Russian involvement in the failure of GPS navigation systems on the plane carrying von der Leyen.