KYIV (Ukraine)(National times)- An overnight Russian drone attack on Kyiv killed three people and wounded dozens, including seven children, Ukrainian officials said on Sunday. Moscow has intensified aerial attacks on Ukraine, including on its energy infrastructure as the war enters a fourth winter and as Kyiv’s allies try to ratchet up pressure on Russian economy with new sanctions. On Saturday night into Sunday, “three people were killed and 31 others were wounded in the Russian attack in Kyiv alone, including seven children,” Ukrainian President Volodymyr Zelensky said in his daily address. He added that “in just one week, the Russians have used almost 1,200 strike drones and 50 missiles of various types against Ukraine, most of them ballistic”. “Protection against such a threat can only be a joint effort — no nation in the world should be left alone to face this.” Kyiv Mayor Vitali Klitschko said earlier that drone fragments fell onto a nine-storey residential building in the northeastern Desnyansky district, sparking fires in apartments on several floors. Fragments damaged another nine-floor block in the same district, where five people were rescued, he said. And more drone fragments fell on a 16-storey residential block in the northern Obolonsky district, damaging an apartment, Klitschko said. The strikes came a day after other Russian drone and missile strikes killed four and wounded around 20 others in Kyiv, according to Ukrainian authorities. On Saturday, US President Donald Trump played down prospects of a summit with Russian leader Vladimir Putin, saying he was “not going to be wasting my time”. The discussions were expected to continue on Sunday.