The UK military is putting a new focus on trench warfare after seeing what's happening in Ukraine

• The UK is putting new focus on preparing its troops for trench warfare.
• That's because it is looking at how widely they are used in Ukraine, British officers told BI.
• Trench warfare may have been somewhat "consigned to history," one said — but no longer.

The UK military is putting a renewed focus on preparing for trench warfare after observing the fight between Russia and Ukraine.

Russia's invasion of Ukraine has brought trench warfare back to Europe, with both sides digging vast networks of fortifications.

The UK military, which has been supporting Ukraine and training some of its soldiers, has taken note, officers told Business Insider.

They spoke during a training session in southern England where British soldiers were helping train Ukrainians who have been fighting on the front lines.

Lt. Col. Wilson, the commanding officer for training and delivery at the site, told BI that "The UK is now investing in its approach for looking at trench warfare.

"Elements of digging in have always been part of training, but now there's a more renewed focus on how trench warfare has evolved," he said.

At the request of UK Ministry of Defence, the officers featured in this article are only referred to by their surnames.

Britain helped pioneer trench warfare in World War I, where years of bloody conflict with Germany cost the UK hundreds of thousands of men and left a permanent scar on the nation.

"Trench warfare has clearly been around for over a century," Wilson said, "and perhaps it had been consigned to history in some view, but now it's very much back in focus and particularly when you layer that with the drone threat."

Drones have been a defining feature of the war in Ukraine, monitoring the battlefield so totally that soldiers often struggle to move without coming under fire.

That's part of the reason there are so many trenches in Ukraine — they are one of the few places soldiers can hide safely.

Wilson said that Britain had "not focused" on trench techniques much in the past decade, where it face a very different kind of foe in Iraq and Afghanistan.

"So our training then was appropriately focused around that environment, the counterinsurgency," he said.

Because of Ukraine, "the extensive use of trenches has brought that again to the fore."

Wilson said that his colleagues who train British infantry "are now looking at trenches, at how we fight against them, but also how we fight from them."

Other NATO members are also training troops on trench warfare, citing its resurgence in the war in Ukraine.

Trench fighting is also a major focus when the British are training Ukraine's soldiers, some 30,000 of them so far.

Both Wilson and another officer, Lt. Col. Davidson, told BI that the British led-training operation, called Operation Interflex, is a mutually beneficial exercise — Ukraine can ask for help with the skills it most needs, while the UK picks up invaluable tips about fighting Russia.

Davidson, the Deputy Commander of Operation Interflex, told BI that Britain and the partner countries helping with the training realized early in the program that "we had doctrine that was dated" on trench warfare.

The Ukrainians were quick to point that out, he said, and the UK changed its offering.

Wilson said the training changes almost in real time.

"Things that are happening on the battlefield today, yesterday, we were able to implement some of those changes really quickly."

Davidson said that as the UK and its allies train Ukrainians, "we're learning as much off of them as they are off of us."