Russian attacks on nine regions of Ukraine knocked out power to hundreds of thousands of households and wounded at least 15 people, officials said Friday, as a new report showed that civilian casualties from Russia’s invasion have climbed steeply. The latest aerial strikes on civilian targets came amid mounting fears that a sharp deterioration in relations between Ukraine and the United States this week could leave Ukraine further exposed to Russia’s escalating assaults with winter approaching.

Meanwhile, Russia’s military chief reported to President Vladimir Putin on Friday that the military has allocated the necessary assets to press its aerial campaign against Ukraine’s energy system. Russia’s heavy bombardment of the power grid before cold weather arrives has been an annual feature of the war, aiming to wear down Ukraine’s appetite for the fight by denying civilians heat and running water. Ukrainian officials have warned that Russia is stockpiling ballistic missiles for more attacks in the coming months.