Kyiv: President Volodymyr Zelensky informed Ukrainians in his latest video address that Russia's retreat from northern portions of the nation was "slow but noticeable," and that Russian forces were withdrawing after conflicts or of their own volition.

"We're moving forward, cautiously," he added, adding that mines posed a threat to buildings, vehicles, and even bodies.Zelenskyy warned once more that the situation in the east was "very challenging," with Russia assembling its forces and "preparing for further heavy attacks."

Ukraine was planning a "active" defence, he stressed, emphasising that "heavy battles are ahead." We can't believe we've already passed all of the tests."

Zelensky cautioned locals to stay wary of land mines as Russian forces retreated from the north, leaving behind "a complete mess."

"They're mining the entire region, residences, mining equipment, even the bodies of individuals who were killed," he said.

He asked residents to postpone returning to regular life until they were satisfied that the mines had been cleared and the danger of bombardment had passed.

IOW says Russia will conquer Maripoul

Meanwhile, the Institute for the Study of War, a think tank based in the United States, has issued an assessment of what Russia's apparent withdrawal from Ukraine's north implies about Moscow's military strategy.

Russia's "primary effort is now centred on eastern Ukraine," according to the IOW, with the goal of taking Mariupol as well as the entirety of Donetsk and Luhansk.

According to its analysts, Russia will conquer Mariupol "in the coming days," but will continue to suffer enormous fatalities.

"The Kremlin will continue to pour reinforcements (including low-quality individual replacements from Russia and injured units redeployed from northeastern Ukraine) into operations in eastern Ukraine," IOW added.