The defense of Lisichansk, the last city in the Lugansk region that it still holds, has become much weaker, CNN reports.. For weeks, Russian forces have been trying to destroy Ukrainian defensive positions south and east of the city in an attempt to encircle and cut off the Ukrainian troops tasked with holding it..

Over the past couple of days, the Russians have advanced, taking several villages south of Lysichansk, although not without losses from Ukrainian artillery fire.. Indeed, the Ukrainian military claims that some Russian battalion tactical groups are being enlarged or withdrawn to restore their combat capability..

The Institute for the Study of War, in its latest daily battlefield analysis, says the Russian breakthrough from the south means they "

All settlements lost by the Ukrainian authorities on Wednesday are located on the western bank of the Seversky Donets River, within 10 kilometers from the southern outskirts of the city.

“The Russians are approaching Lisichansk, having entrenched themselves in nearby settlements. The city is being bombarded by aircraft,” said Sergei Gaidai, head of the Luhansk Regional Military Administration..

Gaidai admitted that it was " “The enemy entered Toshkovka, which made it possible to intensify fire on other settlements”.

According to him, Russian troops have entrenched themselves in several villages immediately south of Lisichansk, including Ustinovka, Podlesnoye and Mirnaya Dolina, and are advancing towards Belaya Gora.. “It’s not easy for our soldiers to keep the defense,” he admitted..

Throughout its campaign, Russia used heavy bombing tactics before attempting to capture territory.. Gaidai's comments suggest that Ukrainian defenses around Lysychansk have begun to succumb to much more Russian firepower after weeks of bombing..

Ukrainian forces continue to fight on the outskirts of the neighboring city of Severodonetsk and in the surrounding communities, and they also benefit from the high ground in Lysichansk.

But their already compromised supply lines are becoming weaker, and the power of Russian firepower is destroying defensive positions..

The setbacks suffered over the past few days after weeks of stubborn resistance have likely been the most difficult week for the Ukrainian military since the surrender of the last defenders of Mariupol.

Attacks near Lysychansk come in tandem with renewed Russian attempts to cut the highway leading west to Bakhmut, a key communications route for Ukrainians. In some places, Russian forces are within a few kilometers of the highway..

Ukrainian defenses of Severodonetsk and Lysichansk have absorbed the firepower of many Russian units and weakened their advance efforts in the neighboring Donetsk region.. However, the Russians are still able to draw on reserves located in nearby areas of southwest Russia while some of Ukraine's best units are severely depleted by months of rocket, artillery and air attacks..

But if the Ukrainians decide to dig in around Lysichansk, taking it will likely require a significant Russian effort, possibly within a few weeks.. By that time, it may resemble the destroyed Severodonetsk, Popasnaya and Mariupol.