In a statement posted to his Telegram channel, a city mayor Vitali Klitschko said that missiles had been fired at the city's western city of Lviv.
There was a thick smoke above the Darnytskyi district in eastern Kyiv, where Klitschko said rescuers and paramedics were on the scene. The governor of Lviv region, Maksym Kosytskiy, said in an online statement that an air raid had been launched on the city.
The attacks came after Russia's defense ministry vowed to increase missile strikes on Kyiv after weeks in which the city had begun to recover.
The Kremlin sent a formal diplomatic note to the United States warning that American and NATO shipments of the most sensitive weapons systems to Ukraine could bring unpredictable consequences and added fuel to the conflict.
A White House official confirmed the contents of the note first reported by The Washington Post, but NBC News hasn't seen the note.
Explosions rocked the Darnytskyi district on the outskirts of Kyiv and an air raid was launched on the western city of Lviv early Saturday, Ukrainian officials said.
Attacks came after Russia's Defense Ministry promised to step up missile attacks on Kyiv in response to Ukraine's alleged assaults on Russian territory.
Russian troops have hampered the ability to get humanitarian aid into Ukraine by destroying bridges, employing land mines and abandoning vehicles, Britain's defense ministry said in an intelligence briefing.
Biden genocide comment raised concerns among some U.S. officials President Joe Biden's statement last week that Russia is committing genocide in Ukraine and has so far not been corroborated by information collected by U.S. intelligence agencies. Two officials said Biden's seemingly offhand declaration made it hard for the agency to do its job, because of the State Department's tasked with making formal determinations of genocide and war crimes through an independent legal process. U.S. intelligence agencies collect information when allegations are made of actions that could amount to genocide, but policymakers are the ones who decide whether or not to declare it. Intelligence reports on Ukraine do not support a genocide designation, officials said. Roads in Ukraine have been devastated by the war launched by Russia, which is causing a significant challenge to get humanitarian aid to parts of the country, the United Kingdom defense ministry said on Saturday. Russian troops have made the damage worse by destroying bridges, employing land mines and abandoning vehicles along key routes as they withdraw from northern Ukraine, the defense ministry said in its daily update. More than 4.5 million people have fled the country as refugees, according to the United Nations humanitarian office this week. At least 7.1 million people have been internally displaced in Ukraine. The war has caused a humanitarian crisis, officials said.