Anti-tank obstacles are being built on a large scale in many areas controlled by Russia in Ukraine. Photo: Telegram

The British Telegraph newspaper wrote that soldiers of the Ukrainian Armed Forces admitted that they could not penetrate the "incredible" defense line of the Russian army.

"They have incredible trenches and fortifications, minefields, it will be very difficult to penetrate their defenses. In addition, they have good artillery and more than us" - the Commander of the Ukrainian Forces shared.

The Telegraph pointed out that the Russian army had prepared a 965 km long defense line, including a network of trenches, trenches, dragon tooth fortifications, and minefields.

British intelligence assessed that this defense network is called one of the largest military fortification systems in the world.

Researchers say Russian forces have dug such trenches along what they consider important transport junctions, or outside strategic cities. The defensive structures have been observed in the Tokmak and Bilmak areas of Zaphorizzhia province.

Most trenches were built in a zig-zag pattern, which limited enemy visibility and provided additional protection from artillery fragments.

In response to Ukraine's full-scale counteroffensive, Russia has deployed new trenches, anti-tank barriers and fortifications that are mushrooming, stretching from the Russian city of Voronok, across eastern Ukraine and southwest to the Crimean peninsula.