Moscow's two main international airports have announced a flat ban on all carry-on liquids as part of a mass security clampdown ahead of next month's Sochi Winter Olympic Games.
Sheremetyevo and Vnukovo airports handle most of Russia's international air traffic and will receive the bulk of foreign fans arriving for the February 7-23 sports festivities on the shores of the Black Sea.
Their joint move caught many Russians off-guard and sparked a furious online debate about a measure that appears to extend to medication and cosmetics.
Russia this week launched the largest security operation in Olympic history that is meant to ward off the threat of Islamist violence following twin suicide attacks last month in the southern hub of Volgograd.
The December 29-30 bombings left 34 dead and sparked fears of a renewed terror campaign by militants from the nearby North Caucasus who have threatened attacks before and during the Games.