The European Commission said on Monday that its president, Ursula von der Leyen, was en route to Bulgaria when her plane faced deliberate GPS jamming. 

"We can confirm there was GPS jamming but the plane landed safe," said Arianna Podesta, a commission spokeswoman. 

Von der Leyen's plane landed in Plovdiv airport and she is continuing her planned tour of EU countries bordering Russia and Belarus, Podesta said.

The EU chief arrived in Bulgaria on Sunday and met with Prime Minister Rosen Zhelyazkov to discuss European security and defense issues.

Russia suspected of 'blatant interference'

The commission spokesperson said the EU received information from Bulgarian authorities that "they suspect this blatant interference was carried out by Russia."

"We are well aware that threats and intimidation are a regular component of Russia's hostile actions," the spokeswoman added. 

"And, of course, the EU will continue to invest into defense spending and in Europe's readiness even more after this incident." 

Separately, Bulgaria issued a statement saying that "the satellite signal used for the aircraft's GPS navigation was disrupted."

"As the aircraft approached Plovdiv Airport, the GPS signal was lost," the statement said.

The Financial Times reported that the plane had to remain in the air for around an hour longer than planned due to the GPS malfunction. The pilot reportedly decided to land manually in the city of Plovdiv using analogue maps.

The airport in Bulgaria's second-largest city is used by low-cost airlines and for charter flights. 

Western officials have long accused Moscow of waging "hybrid warfare" against European countries, including cyber attacks and acts of espionage and sabotage.

Edited by: Saim Dušan Inayatullah