Ukraine’s drone attacks on Russian refineries have resulted in a fuel crunch in Russia, where the shortage is estimated at up to 20% of demand, Ukrainian Volodymyr Zelenskyy said on Thursday. “According to our data, the enemy’s gasoline shortage is up to around 20% of needs. Estimates vary from 13 to 20%, but it is confirmed that the shortage is already significant. In our view, it is about 20% today,” Zelenskyy wrote on X. “Our weapons are delivering tangible results,” the Ukrainian president…