Ukraine on Wednesday accused Russia of planning to hold a military parade in the captured city of Mariupol on May 9 to celebrate victory over the Nazis in World War II.

Kyiv said an official from Russia's presidential administration had arrived in the strategic southern port city, which has been largely destroyed in Russia's more than two-month invasion of Ukraine, to oversee plans for the Victory Day parade.

"Mariupol will become a centre of 'celebration,'" Ukraine's military intelligence said in a statement on social media.

"The central streets of the city are urgently being cleaned of debris, bodies and unexploded ordnance," it added.

Mariupol is among the most battered cities in Ukraine. A group of Ukrainian forces are still holding out in its Azovstal steel plant.

"A large-scale propaganda campaign is underway. Russians will be shown stories about the 'joy' of locals from meeting the occupiers," the military intelligence statement said.

The Ukrainian military said Tuesday that Russian forces had launched an offensive on Azovstal shortly after the United Nations and Red Cross confirmed that more than 100 civilians had been evacuated from the plant.

On Wednesday, the Kremlin denied Russia was storming the plant.

Russians celebrate Victory Day every year on May 9 with military parades and public events commemorating the anniversary of the Soviet Union's defeat of Nazi Germany in World War II.

Moscow has previously said the purpose of its invasion of Ukraine is to "de-militarise" and "de-Nazify" Ukraine.