Explainer: Why is natural gas still flowing from Russia to Europe across Ukraine?

It's one of the more improbable aspects of Russia's invasion of Ukraine: Even after 2 1/2 years of war and repeated rounds of sanctions, Russian natural gas keeps flowing through Ukraine's pipeline network to customers in Europe.

That hasn't changed despite Ukraine apparently taking control of a gas measuring station near the Russian town of Sudzha as part of Kyiv's push into Russia's Kursk region.

Here are key things to know about the transit of Russian gas through Ukraine.

Who gets Russian natural gas through Ukraine's pipelines?

Natural gas flows from West Siberian gas fields through pipes that pass through Sudzha and cross the Ukrainian border into Ukraine's system. The pipeline enters the European Union at the Ukraine-Slovakia border, then branches off and sends gas to utilities in Austria, Slovakia and Hungary.

Natural gas is used to...