"Today we are on Snake Island, which will never be conquered by the occupiers, like the whole of Ukraine, because we are the country of the brave," he said in a video clip released on social media Saturday.

"I want to thank from here, from this place of victory, each of our soldiers for these 500 days," Zelensky said in the undated clip, in which he was shown arriving on the island by boat and leaving flowers at a memorial.

Moscow captured Snake Island shortly after launching its invasion on February 24, 2022.

A radio exchange went viral in which Ukrainian soldiers told the crew of Russia's attacking warship demanding their surrender to "go fuck yourself".

The Ukrainian soldiers were taken prisoner but later exchanged for Russian captives.

The recording of this verbal exchange has gone around the world and served as a theme for the Ukrainian resistance, even appearing on placards during support rallies abroad and on stamps.

The Russian ship involved, the Moskva, sank in the Black Sea in April following what Moscow said was an explosion on board.

Ukraine said it had hit the warship with missiles.

Ukrainian forces re-captured the island in June last year.