Is Ukraine running out of ammunition?

Nato Secretary General Jens Stoltenberg has warned that the Ukrainian army is consuming significantly more ammunition than could be produced in the West.

The warning comes as Russian forces have stepped up their assault on the city of Bakhmut, which they have tried to capture for more than six months.

So how short of ammunition is Ukraine at the moment, and what kind?

Phillips Payson O'Brien is a professor of strategic studies at the University of St Andrews in Scotland. He explains why that question is difficult to answer.

(Photo: Personnel of the 35th Separate Marine Brigade of Ukrainian forces on duty. Credit: Getty Images)