Video footage posted online by Zelenskiy's office showed the president greeting Frederiksen with a handshake on a snowy street before entering a hospital where they met soldiers wounded in Russia's invasion.
"It is important for our warriors to be able to undergo not only physical, but also psychological rehabilitation," Zelenskiy wrote on the Telegram messaging app. "I am grateful to all the medical workers who care about the health of our defenders. I wish them a speedy recovery!"
The two leaders also visited the Mykolaiv Commercial Sea Port, where they saw oil storage tanks hit by Russian enemy missiles and drones, and a heating point equipped with a water purification and distribution unit under a project implemented with Danish assistance.
Zelenskiy thanked Frederiksen for the assistance provided by Denmark, whose defence ministry said earlier this month that the country would donate 19 French-made Caesar howitzer artillery systems to Ukraine.
The president said he had also met local officials while in Mykolaiv region, which has frequently been under attack by Russian forces since the invasion 11 months ago.
"The region is heroically withstanding all the attacks of the terrorists (Russian forces). During the visit, I held a meeting on the current situation in the region," he wrote.
"We discussed the operational situation in the south of Ukraine, the consequences of Russia's missile and drone attacks."
Talks also covered the state of the region's energy infrastructure and the region's long-term recovery, Zelenskiy said.
(Reporting by Max Hunder; writing by Tom Balmforth; editing by Timothy Heritage)
