Finland reports GPS disturbances in aircraft flying over Russia’s Kaliningrad

Aircraft flying near the Russian enclave of Kaliningrad and near Finland's eastern border with Russia have noticed interference with their GPS signals, according to Finnish authorities.

The interference began soon after Finland's President Sauli Niinistö met Joe Biden in Washington on Saturday to discuss deepening defense ties between Finland and Nato due to Russia's attack on Ukraine.

Prime Minister Sanna Marin told Reuters she had no information about the source of the disturbances, nor about whether they originated in Russia, while the foreign ministry said it was looking into the events.

"If they would be caused by outside influence, it would surely be said publicly," Marin said.

The Kremlin did not immediately reply to a request for comment about the reported interference.

Some of Finnair's Asian flights and most of its European ones go past Kaliningrad, which is sandwiched between Nato members Lithuania and Poland on the Baltic Sea's eastern coast, the company told Reuters.

"Our pilots have noticed interference in GPS near the Kaliningrad area in the past few days," a spokesperson for Finland's national carrier said in an email.

Some 10 aircraft have also reported unusual disturbances in GPS signals near Finland's eastern border with Russia since last Sunday, Finnish Transport and Communications Agency Traficom said on Tuesday.

Traficom said it had asked aviation authorities to alert aircraft pilots to the situation by issuing an official Notice to Airmen (Notam) notification. The disturbances were continuing, it said.

"Flying is still safe. Airlines have operational procedures for such situations if the GPS signal is lost," Traficom's director Jari Pöntinen said in a statement.

Lithuanian airline Transaviabaltika said it had been forced to cancel 18 flights between Helsinki and Savonlinna in eastern Finland after the lack of GPS made it impossible to land because Savonlinna airport does not have alternative navigation equipment.

"We have made three attempts to fly to Savonlinna. So far, we have not succeeded," Rene Must, a manager from Transaviabaltika told Reuters.

Electromagnetic radiation from the sun and signal jamming are the only two reasons that could explain such long-lasting disturbances that affect several planes, director of HybridCoE Jukka Savolainen, a pan-European organisation that seeks to counter hybrid threats, told Reuters.

"States can have systems to see where the jamming comes from if they happen to be turned on and in that direction," he said.