How does the Ukrainian army challenge itself to break through Russian lines?

In the spotlight preparations for the Ukrainian reconquest

The long-announced Ukrainian counter-offensive is taking shape. The fighting in recent days has been more intense in the Donetsk and Zaporija regions. But to allow the Ukrainian tanks to advance, the engineer units will have to open “breaches” in the Russian defensive curtain. The “breaching”, central element of the Ukrainian offensive, is the theme of Lines of Defense.

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