As Russia-Ukraine gas deal ends, who's the biggest loser?

As Russia-Ukraine gas deal ends, who's the biggest loser?
Russia's gas transit to Europe via Ukraine has stopped as planned, after a key transit agreement expired at midnight. The pipeline was one of the last routes delivering Russian gas to Europe, supplying Slovakia and also Hungary -- two countries that have maintained close ties with Russia, despite its invasion of Ukraine. Kyiv had made it clear it would not renew the deal amid the war in the interests of national security.