KYIV, Aug 23 (Reuters) - Ukrainian President Volodymyr Zelenskyy vowed on Tuesday (Aug 23) to restore Ukrainian rule over Russia-annexed Crimea, a move that he said would help re-establish "world law and order".

He told an international conference on Crimea that regaining control of the peninsula - seized and annexed by Russia in 2014 in a move not recognised by most other countries - would be the "biggest anti-war step".

"It all began with Crimea, and it will end with Crimea," Zelenskyy said in an opening address to the Crimea Platform, a forum that seeks to restore Ukraine's territorial integrity and end Russia's annexation of Crimea.

Calling for victory over Russia, he said: "It is necessary to liberate Crimea from occupation ... This will be the resuscitation of world law and order."

Zelenskyy said representatives of about 60 states and international organisations participated in the summit, including about 40 presidents and prime ministers.

Almost all took part online but Polish President Andrzej Duda attended in person. He urged global leaders not to turn a blind eye to what he depicted as Russian aggression, and said there could be no return to business as usual with Moscow.

"Crimea was, remains and will be a part of Ukraine just like Gdansk is a part of Poland, Nice is a part of France, Cologne is a part of Germany, and Rotterdam is a part of Netherlands," Duda said.