State media has reported the Kremlin leader’s first trip to the Russian-occupied territories of Ukraine’s Donbas region since the conflict began.
Mr Putin arrived in Mariupol by helicopter and then drove himself around the city’s “memorial sites”, concert hall and coastline, Russian news agencies said.
He also met with residents in the city’s Nevskyi district.
The Standard has not independently verified these reports.
Mykhaylo Podolyak, an aide to Ukrainian president Volodymyr Zelensky, said: “The criminal always returns to the crime scene… the murderer of thousands of Mariupol families came to admire the ruins of the city and (its) graves. Cynicism and lack of remorse.”
Putin also travelled to Crimea on Saturday in an unannounced visit to mark the ninth anniversary of Russia’s annexation of the peninsula from Ukraine.
It is the closest to the front lines Putin has been since the year-long war began.
The International Criminal Court (ICC) said on Friday it had issued a warrant for the arrest of Mr Putin over alleged war crimes involving the illegal deportation of Ukrainian children to Russia. It means he could now be arrested if he sets foot in any of the court’s 123 member states.
Putin is yet to comment publicly on the ICC warrant.
Mariupol fell in May after one of the war’s longest and bloodiest battles, marking Russia’s first major victory after it failed to seize Kyiv and focused instead on southeastern Ukraine
The Organization for Security and Cooperation and Europe (OSCE) said Russia’s early bombing of a maternity hospital there was a war crime.
Ukraine says around 20,000 people have died in Mariupol during the conflict.
The ICC issued an arrest warrant on Friday against Putin, accusing him of the war crime of illegally deporting hundreds of children from Ukraine, a highly symbolic move that isolates the Russian leader further.
While Ukraine’s President Volodymyr Zelenskiy has made a number of trips to the battlefield to boost the morale of his troops and talk strategy, Putin has largely remained inside the Kremlin while running what Russia calls its “special military operation” in Ukraine.
Kyiv and its allies say the invasion, now in its 13th month, is an imperialistic land grab that has killed thousands and displaced millions of people in Ukraine.
Residents have been “actively” returning to Mariupol, Russia’s Deputy Prime Minister Marat Khusnullin, who accompanied Putin, said.
Mariupol had a population of half a million people before the war and was home to the Azovstal steel plant, one of Europe’s largest.
“The downtown has been badly damaged,” Khusnullin said. “We want to finish (reconstruction) of the centre by the end of the year, at least the facade part. The centre is very beautiful.”
Russian media broadcast videos showing the Russian leader driving a car at night through a built-up area as well as walking into what media said was the philharmonic, restored in just three months.
There was also no immediate reaction to the visit from Kyiv.
Mariupol is in the Donetsk region, one of the four regions Putin moved in September to annex. Kyiv and its Western allies condemned the move as illegal. Donetsk, together with the Luhansk region, comprise most of the Donbas industrialised part of Ukraine that has seen the biggest battle in Europe for generations.
Russian media reported on Sunday that Putin also met with the top commander of his military operation in Ukraine, including Chief of the General Staff Valery Gerasimov who is in charge of Moscow’s war in Ukraine.