Russia is celebrating Victory Day, with 29 foreign leaders including the Chinese President Xi Jinping joining Vladimir Putin in Moscow to commemorate the Soviet Union's part in the defeat of Nazi Germany 80 years ago.

But is President Putin about to enjoy his own victory if the US pulls out of peace negotiations over the war in Ukraine? 

For the latest episode of The Fourcast, Krishnan Guru-Murthy talks to one man who thinks President Trump is doing everything in his power to make that happen.

The writer, historian and activist Vladimir Kara Murza has been poisoned and imprisoned for his anti-Kremlin campaigns. He was released from a Siberian jail last year as part of a prisoner exchange.

Produced by Calum Fraser, Toby Bakare, Rob Thomson