Russia's extensive defenses are forcing Ukraine to clear a path 10 miles wide for full-scale attack.
Ukraine needs the space to protect its Western-made tanks and vehicles, The Wall Street Journal reported.
Troops appeared to have pushed into Russia's main defensive line southeast near Zaporizhzhia.
Ukraine faces a daunting challenge in its counteroffensive as it pushes through Russia's defenses and clears a path to get its troops behind the front.
But that route will need to be at least 10 miles wide to protect prized Western-made tanks and armored vehicles from powerful Russian artillery.
Combat veterans told The Wall Street Journal that Ukraine will need as much space as possible to keep assets such as its US-provided Bradley fighting vehicles and German-made Leopard tanks safe as they move deeper into Russian-occupied territory.
Earlier this week, Ukraine appeared to make major progress in busting Russia's extensive defenses in the country's southeast near Zaporizhzhia, with Ukraine's defense minister Oleksii Reznikov saying that Ukraine's forces "broke the first line" and would be expanding their foothold.
Geolocated footage showed Ukrainian infantry advancing to the northwest of Verbove, a small village east of the newly liberated Robotyne and southeast of Zaporizhzhia on the Dnipro River.
—Emil Kastehelmi (@emilkastehelmi) August 30, 2023
While it's not clear exactly which areas Ukraine controls, the footage and movement seem to suggest that Russian control over the outskirts of the town is "degraded," according to an update from the Institute for the Study of War.
The General Staff of the Armed Forces of Ukraine said troops had also advanced south of Robotyne.
Now, Ukraine will need to clear that 10-mile path in order to successfully breach past Russian defenses. If it can't, its armor and vital Western assets will be vulnerable to Russian counter-battery fire, missiles, and artillery.
Along the way, Ukrainian forces face Russia's formidable defenses: landmine fields that stretch for miles, deep trenches, "dragon's teeth" obstacles to block vehicles, and anti-tank ditches that render Western armor helpless.
Russian counterstrikes could wreak havoc on Ukraine's ability to cut through larger swaths of territory towards the Sea of Azov and pummel Russian forces that have been grouped up along the south near Mariupol.
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