Despite the changes in warfare, Russian forces retain the ascendancy and are making slow but steady advances in the east and north of Ukraine. Russia has also caught up in UAV technology after falling behind early in the war, according to military analysts, and like its enemy is churning out drones domestically at a rate of millions a year.

Russia targeted Ukraine with more than 1,800 drones, 1,200 guided aerial bombs and 83 missiles of various types, President Zelenskyy said.

A Russian official says American Daniel Martindale has been rewarded with citizenship for spying on Ukraine, "by decree of our President Vladimir Putin."

Daniel Martindale helped the Kremlin target Ukrainian troops and was then spirited out of eastern Ukraine by Russian special forces.

Two Russian agents were killed by Ukrainian security forces Sunday following reports that the Russian operatives assassinated Ukrainian Colonel Ivan Voronych.

Ukraine's security agency says it has killed Russian agents suspected of assassinating a senior officer in Kyiv.

Zelenskyy has emphasized the importance of expanding production to counter Russia's invasion and strike deeper into Russian territory.

Russia and Ukraine have exchanged more bodies of their war dead, a Kremlin aide said on Thursday, part of an agreement struck at the second round of peace talks in Istanbul in June.