LONDON -- Russia launched an unusually large drone attack on Ukraine overnight into Tuesday, shortly before Moscow's representatives opened talks with a U.S. delegation in Saudi Arabia on ending Russia's three-year full-scale invasion of Ukraine.

A Russian drone has hit the protective shelter over Chernobyl's damaged nuclear reactor, Ukrainian President Volodymyr Zelensky has said. The overnight strike at the site of the world's worst nuclear accident caused a fire that has since been extinguished, he added.