Moscow’s drone strikes have grown exponentially thanks in part to a deal with Iran to produce its Shahed drones on Russian soil. An attack overnight that focused on Kyiv killed at least 15.

There were no reports of any damage in Moscow on Sunday, but the Ukrainian attack led to a short-lived fire at the Azot chemical plant in the neighbouring Tula region, injuring two people, and seven drones were destroyed above the Kaluga region, regional governors said.

A spat over the latest planned prisoner swap escalated as the Kremlin and Kyiv exchanged accusations over an ongoing delay.