A top NATO official has warned Europe to be prepared for all out conflict with Russia within the next 20 years. But the “second army of the world” which boasted of taking Kyiv in 3 days is said to have suffered more than 300,000 casualties since the full scale invasion of Ukraine.

So how long can President Putin continue his war of attrition? We spoke to professor Sergey Radchenko from Johns Hopkins university.

We began by asking him if he thought President Zelenskyy’s optimism about future Western support was misplaced – given the possibility of donor fatigue.