President Biden said the United States would cut off Russia's largest banks and companies from Western financial markets and restrict exports of technology to Russia.

Prime Minister Boris Johnson said Britain would increase sanctions against Russian banks, companies and oligarchs, restrict technology exports into Russia, and ban the country's airline, in retaliation for Russia's invasion of Ukraine.

Ukraine's ambassador to the United States said Russia's attacks have killed at least 40 Ukrainian solders and dozens of civilians. She added that hospitals and the sealed Chernobyl nuclear disaster site were among the areas hit.

President Biden plans to impose sanctions on Russia for what he called an 'unprovoked and unjustified' attack on Ukraine.

On Russian state television, President Vladimir V. Putin of Russia declared the start of a 'special military operation' in Ukraine, and falsely accused its government of committing genocide.

During a heated exchange at the United Nations Security Council, Ukraine's ambassador accused Russia of declaring war against his country, which the Russian ambassador denied.

In a televised speech, President Volodymyr Zelensky of Ukraine addressed the people of Russia and said his country had no grievance with them and meant them no harm, even as the Kremlin appeared poised to invade.

Ukraine called for the emergency meeting after Russia said the leaders of two separatist regions in Ukraine had requested the Kremlin's protection from Ukrainian 'aggression.'

Boris Johnson defended the scope of Britain's sanctions against Russia, telling lawmakers that 'there is more to come.' The prime minister also said regulators would investigate the Russian TV news channel, RT.

Brett Hankison, a former Louisville, Ky., police detective, is accused of recklessly endangering Breonna Taylor's neighbors during the police raid that killed Ms. Taylor in March 2020.