Why has the conflict in Ukraine seen a return to trench warfare?

Trench warfare is a phrase many associate with the First World War, with troops hunkered down in deep trenches.

Again, most people would presume those days are gone but the war in Ukraine has shown trench warfare is far from obsolete.

Neither Russia nor Ukraine has the supply of sophisticated weaponry and resources needed for modern, mobile warfare, instead relying on large numbers of volunteers who don’t understand more advanced military strategies.

• UK sending long-range Storm Shadow missiles to Ukraine
• 'This is not a film': Foreign Secretary warns no 'guarantees' of Ukrainian success in counteroffensive
• New $1.2bn US aid package to Ukraine includes air defence and artillery support

This puts trenches at the heart of the battle again.

Now, many military strategists are having to consider how trench warfare will play a role in the future.

Forces News spoke to Justin Crump, a former British Army tank commander, and Dr Stephen Bull, a historian, to find out more.