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.

Russia and Ukraine struck each other with hundreds of drones on Sunday, throwing Russian air travel in disarray, shortly after Ukrainian President Volodymyr Zelenskyy announced deals with Western partners that would allow Kyiv to scale up drone production.

It was the latest in a series of almost weekly large-scale missile and drone attacks. President Trump said he “didn’t make any progress” with President Vladimir V. Putin of Russia.