Russian forces have withdrawn from Snake Island, a strategic Black Sea outpost, the head of the Ukrainian President's office, Andriy Yermak, said on Thursday.

"KABOOM! No Russian troops on the Snake Island anymore. Our Armed Forces did a great job," Yermak wrote on Twitter. However, Reuters was not immediately able to verify Yermak's statement.

Russia also announced it was pulling its forces from Snake Island, calling it a "goodwill gesture" to allow Kyiv to export agricultural products.

"On June 30, as a gesture of goodwill, the Russian armed forces completed their tasks on Snake Island and withdrew a garrison stationed there," the Russian Defense Ministry said in a statement.

The ministry said the move showed Russia is not impeding United Nations efforts to organize a humanitarian corridor to export agricultural products out of Ukraine.

Snake Island, which Russia occupied on the first day of its invasion, achieved worldwide fame when Ukrainian border guards stationed there rejected a Russian warship's demand for their surrender.

In March, the Ukrainian soldiers were reported dead on the small Black Sea island, who Kyiv planned to posthumously honor, are said to be "alive and well" after being captured by Russian troops.

"We are very happy to learn that our comrades-in-arms are alive and well," the Ukrainian navy had said on Facebook. The Ukrainian soldiers had surrendered after running out of ammunition, it also had said.

Russia had destroyed the entire infrastructure of the island. However, the Russian military later shared pictures of the prisoners and Russian state TV later showed what it claimed was footage of the soldiers alive in custody.