The Ukrainian presidency distributed images of President Zelenskyy singing the national anthem with his hand over his chest as the country's blue and yellow flag was hoisted next to Kherson's main administrative building.

In Kherson, Zelensky said that "the price of this war is high".

"People are injured. A large number of dead. (Russian forces) have left or escaped -- we believe that they have escaped because our army has surrounded the enemy and they were in danger," Zelensky said.

"There were fierce battles, and the result is -- today we are in Kherson region."

"This is what the Russian Federation did in our country, it showed the whole world that it can kill. But all of us, our armed forces, our National Guard and intelligence (services) have shown that it is impossible to kill Ukraine," Zelenskyy said.

Russian forces fled Kherson last week in their third major retreat since invading Ukraine in February, and the first time they have abandoned such a large city.

The city of Kherson was the first major urban hub to fall to Russian forces and the only regional capital Moscow's troops gained control over.

Its recapture opens a gateway for Ukraine to the entire Kherson region, with access to both the Black Sea in the west and the Sea of Azov in the east.

The region was one of four that the Kremlin announced in September were annexed and part of Russia. Russian President Vladimir Putin vowed to use all available means to defend them from Ukrainian forces, hinting at the use of nuclear weapons.

The Zelenskyy visit came as Russian newspaper Kommersant cited a source as saying delegates from Washington were meeting on Monday in the Turkish capital Ankara with Russian delegates reportedly including Sergei Naryshkin, head of the SVR foreign intelligence agency.

The Kremlin said it could neither confirm nor deny the report and a Turkish official declined comment. But flight-tracking data showed a Russian plane had landed in Ankara which Yoruk Isik, an Istanbul-based geopolitical analyst at the Bosphorus Observer consultancy, said was only used by top officials.

U.S. Central Intelligence Agency Director William Burns is in Ankara to speak with his Russian intelligence counterpart to convey a message on consequences of any use of nuclear weapons by Russia, a White House official said on Monday.

News emerged this month that U.S. national security adviser Jake Sullivan has engaged in confidential talks with senior Russian officials, aimed at lowering the risk of a broader war over Ukraine.

This report was compiled using data from Reuters and Agence France-Presse