Day 49 of the Invasion of Ukraine: Medvedchuk arrested, Biden called Putin's actions Genocide

Here are the most important events of the last hours related to the war in Ukraine.

Ukraine's security service announced it has arrested Putin's top pro-Russian politician and personal friend, Viktor Medvedchuk. The leader of the opposition party was under house arrest on suspicion of treason but escaped shortly after the Russian invasion.

President Zelensky offered Russia to exchange him for captured Ukrainians. Earlier on Tuesday, he said new mass graves were being discovered "almost daily" in the formerly occupied areas.

Russia and Ukraine are gathering forces in the eastern Donbas region. Satellite images show the movement of Russian troops and equipment around at least three locations along the border with Ukraine.

The United States has said it cannot confirm reports that Russia used chemical weapons during the siege of Mariupol. However, US Secretary of State Antony Blinken said that "the United States has reliable information that Russia may use ... chemical agents in its offensive to capture the besieged Ukrainian city of Mariupol."

President Putin has made a rare public appearance with Belarusian leader Alexander Lukashenko. He said the peace talks had reached a stalemate after Ukraine made "false allegations" of war crimes.

Putin described Russia's military goals in Ukraine as noble. He said Russia would continue its "special operation" to protect Russian speakers in eastern Ukraine.

US President Joe Biden and British Prime Minister Boris Johnson spoke by telephone, discussing how to increase economic pressure on Russia and end the West's dependence on its oil and gas.

The conversation took place...