There is too little data to generate a comparable live estimate for Ukraine. However, a catalogue of the known dead and missing from UAL osses, a website, implies that between 73,000 and 140,000 Ukrainian soldiers have died since the invasion began.

Russia now has 111,000 soldiers in the Pokrovsk area, which it has been trying to seize since early last year, Ukraine's top armed forces commander Oleksandr Syrskyi said last week, describing dozens of battles in the area every day.

While Russia's overnight drone and missile attacks on Ukraine have hit record levels, on the ground its military is claiming territorial gains. Last month Russian forces seized 556 sq km (215 sq miles),