At least seven people were killed when Russia launched a barrage of drones across Ukraine overnight, according to local Ukrainian officials and emergency services

Cross-border drone attacks killed civilians in both Ukraine and Russia overnight into Sunday, according to local officials.

Sunday's attacks occurred ahead of ceasefire negotiations in Saudi Arabia in which Ukraine and Russia are expected to hold indirect U.S.-mediated talks.

MOSCOW -- Kremlin spokesman Dmitry Peskov said on Sunday that achieving a ceasefire in the Russia-Ukraine conflict remains a complex challenge requiring substantial efforts, emphasizing that negotiations are still in their early stages.

Ukraine has key demands from Russia as well. Kyiv refuses to cede more territory to Moscow, including those in partially occupied regions. Also, Ukraine is seeking the return of children illegally deported to Russia and thousands of civilians detained in Russian prisons.