Russian air defence units downed six Ukrainian drones headed for Moscow on Sunday, mayor Sergei Sobyanin said.

Ukraine said it struck a Russian air base on Saturday, while Russia continued to attack Ukraine with hundreds of drones overnight as part of a stepped-up bombing campaign that has dashed hopes for a breakthrough in efforts to end the more than 3-year-old war.

Ukrainian drone attacks for the second day in a row severely disrupted flights throughout Russia, with the largest airports serving Moscow and St. Petersburg among those forced to restrict activity throughout July 6.