Russia is believed to have jammed the satellite signal on an RAF plane taking Defence Secretary Grant Shapps back to the UK from Poland.
The GPS signal was interfered with for about 30 minutes while the jet flew near the Russian territory of Kaliningrad on Wednesday, according to a report in The Times.
Mobile phones could not connect to the internet and the aircraft, a Dassault 900LX Falcon jet, had to use alternative methods to determine its location.
Mr Shapps, who was travelling with his staff and several journalists, was returning from a military training site in Orzysz, Poland, where he had watched hundreds of troops participate in Steadfast Defender, the biggest NATO exercise since the Cold War.
Experts told The Times it was not clear whether Mr Shapps was targeted but the plane’s flight path could be seen on aircraft tracking websites.
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A defence source told the newspaper: “While the RAF are well prepared to deal with this, it still puts an unnecessary risk on civilian aircraft and could potentially endanger people’s lives.
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“There is no excuse for this and it’s wildly irresponsible on Russia’s part.”
Prime Minister Rishi Sunak’s spokesperson confirmed the incident happened on Wednesday but added it was “not unusual”.
They said: “It didn’t threaten the safety of the aircraft and it is not unusual for aircraft to experience GPS jamming near Kaliningrad, which is of course Russian territory.”
The Ministry of Defence has not commented.
Kaliningrad is separated from the Russian mainland, and is situated between Poland and Lithuania.
It is Russia’s only ice-free port on the Baltic Sea.
The UK’s relationship with Russia has deteriorated in recent years, particularly after the country launched a full-scale invasion of its neighbour Ukraine in February 2022.