Russia does not intend to use Ukrainian President Volodymyr Zelenskyy's “peace formula” as a basis for negotiations, Foreign Minister Sergey Lavrov said on Thursday.
Ukraine reported a Russian missile strike on Thursday morning and blasts were heard in several cities as air defence systems shot down missiles.
Moscow believes Kyiv is still not ready to hold peace talks, Russia's RIA news agency reported.
Mr Lavrov said Ukraine's idea of driving Russian forces out of eastern areas and Crimea with western help was “an illusion”.
He emphasised Moscow's position that talks cannot take place until Kyiv recognises Russia's annexation of four Ukrainian regions.
“Our absolute priority is four new Russian regions,” Mr Lavrov said.
"They should become free from the threat of Nazification that they have faced for many years.”
On Thursday, Ukrainian presidential office adviser Oleksiy Arestovych wrote on Facebook that more than 100 missiles had been fired at the country, in several waves, and air raid alarms could be heard across the country.
Blasts were heard in Kyiv, Zhytomyr and Odesa, Reuters reported.
Power cuts were announced in the Odesa and Dnipro regions to help minimise damage to the country's energy infrastructure.
Mr Lavrov said on Wednesday he was convinced that Moscow would achieve its goals in Ukraine.
“I am convinced that thanks to our perseverance, patience and determination, we will defend the noble goals that are vital for our people and our country,” he said in an interview broadcast on national television.
The recently liberated southern city of Kherson has remained under bombardment from Russian forces, which retreated to the eastern bank of the river when the city was retaken last month.
On Wednesday, the shelling hit the maternity wing of a hospital, although no one was hurt, said Kyrylo Tymoshenko, Mr Zelenskyy's deputy chief of staff.
Staff and patients were moved to a shelter, Mr Tymoshenko said in a post on Telegram.
“It was frightening ... the explosions began abruptly, the window handle started to tear off ... my hands are still shaking,” Olha Prysidko, a new mother, told Reuters.
“When we came to the basement, the shelling wasn't over. Not for a minute.”
Moscow has repeatedly denied taking aim at civilians.
'We have not lost our humanity'
Mr Zelenskyy urged Ukrainians in a video address to hug loved ones, tell friends they appreciate them, support colleagues, thank their parents and rejoice with their children more often.
“We have not lost our humanity, although we have endured terrible months,” he said. “And we will not lose it, although there is a difficult year ahead.”
Russia invaded Ukraine on February 24 in what Russian President Vladimir Putin called a “special military operation” to demilitarise its neighbour.
Ukraine and its western allies have denounced Russia's actions as an imperialist-style land grab.
Sweeping sanctions have been imposed on Russia for the war, which has killed tens of thousands of people, driven millions from their homes, left cities in ruins and shaken the global economy, driving up energy and food prices.
Russian gas exports to Europe via pipelines collapsed to a post-Soviet low in 2022 as its largest customer cut imports due to the Ukraine conflict and a major pipeline was damaged by mysterious blasts, Gazprom data and Reuters calculations show.
