Russia is marching their soldiers into a 'death trap' by besieging Kyiv: Former military officer
A Ukrainian interior ministry hand out photo shows the moment an apparent Russian strike knocked out television broadcasts in Kyiv. (UKRAINIAN INTERIOR MINISTRY PRESS SERVICES/AFP)

On Wednesday's edition of CNN's "The Situation Room," retired Maj. John Spencer outlined how a siege of the Ukrainian capital of Kyiv could quickly turn into their worst nightmare.

"You say Ukrainians have an advantage when it comes to urban warfare, but they need to make their cities, and I'm quoting you now, 'a maze of hell,'" said anchor Wolf Blitzer. "What does that look like?"

"Sun Tzu said the worst thing a military could do is besiege a walled city," said Spencer. "Cities are death traps for militaries. And especially ones that don't perform well. So, a maze of hell means every road, every alley, every door is blocked with something and you don't — and the soldiers won't know it doesn't have to be a sniper, a rifle. I know from personal experience, fighting in urban terrain is the worst thing they want to do, and I think they will experience that soon."

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"Yeah, they're building Molotov cocktails," noted Blitzer. "You often write — you write about wish lists. What should be on the Ukrainian wish list right now? What do they need from the U.S., for example, when it comes to urban warfare, which is anticipated?"

"Well, they're the ones in the fight, so they're the ones who know what they need," said Spencer. "I've been studying urban warfare for over a decade, I've had my own experiences. It might not make common sense, the kind of stuff that I want to turn my city into a fortress. I'm talking things like hand grenades, things like mines. Of course they need, from anybody, the high-end stuff like the Javelin, one of the most lethal anti-tank things in the world. They also need things to turn every street into a living hell. Like, you know, from even experiences in Iraq — mines, Claymores, wire."

"I've had this long list of how to turn my city into a fortress," added Spencer. "Because really, that's what that convoy is doing. That convoy is the siege convoy. And that siege, they won't circle and wait. They'll circle and attempt to find a weakness. Once they find that weakness, they'll punch in through that one direction. So every hour they can't get there, that's more time. And we're seeing that, which is great, in photos. They're blocking the streets with cars and buses. They're preparing innovative ways to turn it into an ugly situation."

Watch below:

Ret. Maj. John Spencer outlines how Ukrainians can force Russians into a "death trap"