Putin moves Russia's nuclear forces to "special alert”, in response to what he described as “aggression” from Nato countries. Meanwhile as fighting continues in the streets across Ukraine’s biggest cities, President Zelensky says his delegation will meet with Russia at the Belarus border for talks.

Is President Putin using his nuclear arsenal as a conflict deterrent or as a threat to the West? Victoria and Gabriel are joined by the former director of the UN Institute for Disarmament Research, Dr Patricia Lewis.

And as hundreds of thousands flee Ukraine, we hear from Newsnight’s Lewis Goodall from the border in Poland, where he’s been speaking to families trying to make their way to safety.

This episode of Ukrainecast was made by Daniel Wittenberg with Phil Marzouk and Caitlin Hanrahan. The studio manager was Stephen Bailey. The editor is Jonathan Aspinwall.