(upd 14:27) The GPS system of the aircraft of European Commission President Ursula von der Leyen was jammed while she was on a flight to Bulgaria yesterday, Sunday, an EU spokesman said today, Monday, confirming media reports.

"We can indeed confirm that there was a blockage, but the aircraft landed safely in Bulgaria. We have received information from the Bulgarian authorities that they suspect that the blockage was due to Russian interference," the spokesman added.

The Russian government did not immediately respond to a request for comment.

The EU did not provide further details, but the spokesman said the incident would reinforce the bloc's unwavering commitment to strengthening defense capabilities and support for Ukraine against Russian aggression.

In a statement, the Bulgarian government said the GPS signal was lost as Von der Leyen's plane approached the southern city of Plovdiv, prompting air traffic controllers to switch to ground-based navigation systems to ensure a safe landing.

One hour above the airport

This was preceded by a Financial Times report that reported that a Russian interference attack disabled GPS navigation services at a Bulgarian airport, resulting in the aircraft carrying the President of the European Commission, Ursula von der Leyen, ultimately landing in Plovdiv (known to us as Plovdiv), using non-digital maps.

The GPS in the airport area went out, an official told the FT. After circling the airport for an hour, the pilot made the decision to land the plane manually and using non-digital maps, according to reports. It was an undisputed interference, according to officials.

Von der Leyen's plane landed safely at the planned location, the EU spokesman confirmed, adding that an investigation into the incident is underway.

The  Bulgarian Air Traffic Services Authority  also confirmed the incident to the Financial Times.

How is the navigation system affected?

Since February 2022, there has been an increase in incidents of interference, which disrupts accurate reception of [GPS] signals, causing various operational challenges for aircraft and ground systems, according to officials.

So-called jamming, which distorts or prevents access to  satellite navigation systems, has traditionally been used by  military and intelligence agencies  to defend sensitive locations, but can also be used as a means of disrupting civilian life.

Tour to frontline states

Von der Leyen was flying from Warsaw to the central Bulgarian city to meet the country's Prime Minister Rosen Zhelezkov and visit a munitions factory.

It is noted that the President of the Commission began a tour of the so-called frontline states on Friday, to reassure them of Europe's support against Russian aggression and to boost defense spending, according to a statement from the European Commission.

He visited countries bordering Russia or Belarus, as well as Bulgaria, as part of the EU's broader diplomatic campaign on its security and defense since the start of the war in Ukraine.

The tour, which was due to conclude today, Monday, coincides with intensive efforts by US President Donald Trump  to mediate an end to the three-year war.

Despite the intense diplomatic activity of the past few days and the Trump-Putin meeting in Alaska, however, the Russian president has shown no willingness to stop the attacks on Ukraine.

Last week, Russian forces struck Kiev with drones and ballistic missiles, killing civilians, while an EU delegation building in the Ukrainian capital was hit.