Russia says its "special military operation" has entered a new phase in Ukraine. Moscow has shifted its focus to the east, saying the aim is to fully capture two provinces. Elsewhere in Ukraine, blasts have also been heard in Kharkiv in the northeast, Mykolaiv in the south and Zaporizhzhia in the southeast. In the besieged city of Mariupol, Russia gave the last Ukrainian defenders an ultimatum to surrender by noon. Meanwhile, U.S. President Joe Biden is set to hold a call with allies on Tuesday to discuss the crisis.