A spokesperson for Russian energy giant Gazprom said on Monday that a mine destroyer discovered at the Nord Stream 1 offshore gas pipeline in 2015 belonged to NATO.
Nord Stream reported on that date in 2015 that a "munitions object" had been cleared by the Swedish armed forces, without giving more detail on the object.
Gazprom spokesperson Sergei Kupriyanov told Russian state television on Monday that a NATO device, called a SeaFox, was retrieved from a depth of around 40 metres (125 feet) and made safe.
"Gas transportation, halted because of the incident, was restored," he said, according to a published extract from his TV appearance.
Gazprom owns 51% in Swiss-based Nord Stream AG, operator of Nord Stream 1.
An international investigation is underway into a rupture, discovered late last month, in the Russian-built Nord Stream 1 and Nord Stream 2 pipelines on the bed of the Baltic Sea.
The pipelines, which have become a flashpoint in the Ukraine crisis, have been leaking gas into the Baltic Sea off the coast of Denmark and Sweden.
Europe suspects an act of sabotage that Moscow quickly sought to pin on the West, suggesting the United States stood to gain.