The country that exports oil to half the world has started rationing fuel for its own drivers. The Russian company Tatneft has imposed a limit across its network of petrol stations throughout Russia - about 20 litres of petrol and 40 litres of diesel per vehicle. When an oil producer starts handing out fuel by the drop, something in the machine is creaking.

Tatneft isn't the biggest player - it holds around 8-9 percent of Russian petrol production, against Rosneft's roughly 35 percent, Lukoil's 20-25 and Gazprom Neft's 12-15. But that's exactly why the move matters: when a mid-sized player imposes a uniform limit across all its locations, that's a stronger signal than the occasional local measures of the others. Lukoil restricted jerrycan sales at certain spots in Moscow and suspended fuel cards in Nizhny Novgorod, while Rosneft quickly lifted some of its restrictions.

The official message is that there's no crisis at the national level, just pressure on supply. Maybe. But rationing is a word governments don't utter lightly, least of all a country that builds its very identity on energy power. When the supplier to half of Europe is counting out litres in front of its own citizens, the question isn't whether there's a problem, but how long it can keep calling it by another name.

For the region, this is a reminder of how fragile energy is even for those we assume have it in abundance. Fuel prices in the Balkans always react to what's happening further away than it looks. Would we behave any differently here if reserves started being measured out? A question worth keeping in mind as we watch rationing turn up where we least expected it.