A central Ukrainian city held vigils on Monday that began three days of mourning for 11 adults and nine children killed by a Russian missile last week, as one of the deadliest attacks on civilians in months jeopardised Washington's ceasefire push.

Anger and outrage are gripping the hometown of Ukrainian President Volodymyr Zelenskyy as it holds funerals for some of the 20 people, including nine children, killed by a Russian missile that tore through apartment buildings and blasted a playground.

Russia has cynically fabricated a story about a NATO officer's meeting allegedly held in a restaurant in Kryvyi Rih that was supposedly targeted in a precision missile strike, said Ukrainian General Staff spokesperson Dmytro Lykhoviy.