Russian President Vladimir Putin signs a law officially quitting the Treaty on Open Skies. (Photo: TASS)

The Treaty on Open Skies, which came into effect in 2002, allows its states-parties to conduct short-notice, unarmed reconnaissance flights over the others' territories to collect data on military forces and activities.

After Washington announced its withdrawal last year, the Russian Foreign Ministry said in January that the country had started domestic legal procedures for the official pullout from the treaty.

The Russian Federation Council, or the upper house of parliament, passed a bill on Wednesday to endorse Russia's withdrawal from the treaty.