LONDON — A plane carrying British Defense Secretary Grant Shapps had its satellite signal jammed as it flew near Russian territory, the government said Thursday.

The government said the Royal Air Force jet carrying Shapps, officials and journalists “temporarily experienced GPS jamming when they flew close to Kaliningrad” on a flight from Poland to the U.K.

The Times of London, whose reporter was onboard, said that for about 30 minutes mobile phones couldn’t connect to the internet and the aircraft was forced to use alternative methods to determine its location.

Shapps visited Poland on Wednesday to see U.K. troops participating in a large NATO exercise, Steadfast Defender.

Kaliningrad is a Russian enclave bordered by Poland and Lithuania, home to the Russian Navy’s Baltic Fleet.

Prime Minister Rishi Sunak’s spokesman, Dave Pares, said “the jamming didn’t threaten the safety of the aircraft at any point.” He said it was not unusual for aircraft to experience electronic jamming near Kaliningrad.

Western officials say Russia has significant electronic warfare capabilities based in Kaliningrad.

Since Moscow’s invasion of Ukraine in 2022, Russia has engaged in GPS jamming in areas from Finland to the Black Sea. A regional Finnish carrier had to cancel flights on one route for a week as a result.