UKRAINIAN president Volodymyr Zelenskyy has visited the recently retaken city of Izium as the country’s flag was raised in front of the burned-out city hall building.

Russian forces left the war-scarred city last week as Ukraine pressed forward in a sweeping counter-offensive that has reclaimed vast swathes of territory in the country’s north-eastern Kharkiv region in a matter of days.

Much of Izium has been devastated during the conflict.

Apartment buildings are blackened by fire and pockmarked by artillery strikes. The entire centre of one residential building had collapsed, a gaping hole and piles of rubble where homes used to be.

“The view is very shocking but it is not shocking for me,” Zelenskyy said in brief comments to the press.

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“Because we began to see the same pictures from Bucha, from the first de-occupied territories … so the same destroyed buildings, killed people.”

Bucha is a neighbourhood near Kyiv where the bodies of civilians, many of them bearing signs of torture, were found dumped in the streets, in mass graves and in yards after Russian forces withdrew hastily in March.

On the northern outskirts of Izium, the remains of Russian tanks and vehicles lie shattered along the road.

“Our soldiers are here. That’s a very important thing. It supports people,” Zelenskyy said. “I see how people meet them. It means that with our army, the life comes back.”

Following the recent gains, a Washington-based think tank, the Institute for the Study of War, yesterday said that the Oskil River appears to be becoming the new front line in the area.

The Oskil River flows south and largely represents the eastern edge of Ukraine’s Kharkiv region.

“Ukrainian forces are continuing localised ground assaults to threaten Russian positions behind the Oskil River,” the institute said.

“Russian troops are unlikely to be strong enough to prevent further Ukrainian advances along the entire Oskil River because they do not appear to be receiving reinforcements,” it added.