Ukrainian President Volodymyr Zelensky warned airlines, insurers and foreign governments on Sept. 1 that Russian airspace is becoming increasingly dangerous because of Ukrainian drone activity, saying it will be effectively closed to civilian aviation.

Ukrainian President Volodymyr Zelensky on Tuesday warned airlines, insurance firms and passengers that Russian airspace would be "completely unsafe" and filled with Ukrainian…

"Today we want to warn every airline that uses Russian airspace, every insurer, everyone who still uses key Russian airports — Russian skies are becoming completely dangerous,"…