Pictured: Russian Forces Dig Trenches in Preparation for Ukraine Onslaught

Russian troops are digging trenches and fortifying their positions in preparation for a possible Ukrainian counteroffensive in eastern Kherson, a U.S. think tank has assessed.

The Institute for the Study of War (ISW), analyzing satellite imagery, said it is clear that the Russian military assesses that Ukrainian forces could eventually cross the Dnieper River and conduct counter-offensive operations in the eastern part of the region.

This could possibly threaten "all of the critical ground lines of communications (GLOCs) from Crimea to the mainland," the ISW said.

Ukrainian soldiers  in Sloviansk, Donetsk region
Ukrainian soldiers train in an abandoned building in Sloviansk in Ukraine's Donetsk region on November 23, 2022 before heading back to the front line. Russian troops are digging trenches and fortifying their positions in preparation for a possible Ukrainian counteroffensive in eastern Kherson, a U.S. think tank has assessed. ANATOLII STEPANOV/AFP/Getty Images

The assessment comes after Russia announced its withdrawal on November 9 from the western portion of the Kherson region after weeks of advances by Ukraine, and as Russia moved to evacuate hundreds of thousands of its residents.

Kherson became the first major region to fall to Russian President Vladimir Putin's forces after the war began. It had been Russia's biggest military achievement of the conflict, in part because of its strategic location and proximity to Crimea.

Kherson is one of four territories that Putin illegally annexed in September following sham referendums.

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In this satellite image, trenches, fortifications and tank obstacles are visible near Velyka Blahovischenka, Kherson Oblast in Russian-occupied Ukraine on November 15, 2022. Maxar Technologies

Satellite images from Maxar Technologies, dated November 15, show Russian forces have been digging trench lines and concentration areas in eastern Kherson since early October in "obvious preparation" for the withdrawal from the west bank of the Dnieper River and Kherson city, the ISW said.

According to the think tank, Russian troops are preparing either to defend in depth or to conduct operational or strategic delay operations.

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In this satellite image, trenches, fortifications and tank obstacles are visible near Velyka Blahovischenka, Kherson Oblast in Russian-occupied Ukraine on November 15, 2022. Maxar Technologies

"Russian forces clearly do not expect to be able to prevent Ukrainian forces from getting across the river, nor are the Russians prioritizing defensive positions to stop such a crossing," experts at the ISW said.

"The Russian military is setting conditions for a protracted defense in eastern Kherson Oblast that could allow the establishment of a solid Ukrainian lodgment on the eastern bank of the Dnipro River."

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Trenches, fortifications and tank obstacles are visible near Stepne in a Russian-occupied area of Ukraine's Kherson Oblast on 15 November 2022. Maxar Technologies

The satellite imagery shows that Russian troops have prioritized digging trenches and erecting dragon's teeth anti-tank defenses along GLOCs that connect Russian forces on the eastern (left) bank of the Dnieper River with southeastern rear areas in Kherson region and Crimea, as well as with eastern rear areas around Melitopol, Zaporizhia Oblast.

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This satellite image shows trenches near Novotroitske, Kherson Oblast in Russian-occupied Ukraine on 15 November, 2022. Maxar Technologies

Russia's military is setting up "layered lines of defense" while ramping up fortifications on and around the Kinburn Spit, suggesting that the leadership views the prospect of a Ukrainian counteroffensive as a "serious threat," the think tank said.

The Kinburn Spit, which is attached to the Kinburn Peninsula, was first seized by Russian forces in June and has remained one of the last occupied territories in southern Ukraine. According to a statement by Ukraine's Operational Command South on November 18, the Kinburn Spit area has been the "focus of enemy's life force, weapons and equipment."

The command said on its Facebook page that Ukrainian armed forces had destroyed part of the the sandy area.

Natalia Humeniuk, spokesperson for Ukraine's southern command, reported on Monday that "hostilities" are currently taking place there.

"This is very difficult work, in particular because of the weather conditions, the geographic location, and the suggestions that Mykolaiv Oblast should become part of the 'grain corridor'," she said.

Newsweek has contacted Russia's foreign ministry for comment.

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