The Ukrainian leader was speaking at the end of a major diplomatic summit in Switzerland, to which Russia was not invited, designed to rally support for Kyiv's proposals on how the war should end.

"Russia and their leadership are not ready for a just peace, this is a fact," Zelensky told reporters at a closing press conference.

A final communique, agreed by around 80 states, reaffirmed a commitment to Ukraine's "territorial integrity" and said dialogue between "all parties" would be needed to end the conflict.

Russia invaded Ukraine in February 2022, unleashing the largest conflict in Europe since World War II.

Its forces still control just under a fifth of Ukraine's internationally recognised territory, including the Crimean peninsula which it annexed in 2014.

Russian President Vladimir Putin on Friday demanded Ukraine withdraw its own troops from the south and east of the country if it wanted the invasion to end.

French President Emmanuel Macron blasted it as a call for "capitulation", while Zelensky rejected the "Hitler"-like "ultimatum".

On Sunday, Zelensky called for a full Russian withdrawal and respect for Ukraine's "territorial integrity".

"Russia can start negotiations with us even tomorrow, without waiting for anything, if they leave our legal territories," he said.

Zelensky also said he would like to see China play a bigger role in discussing a settlement to the conflict.

Beijing, a close political and economic ally of Russia, did not attend the summit in protest at Moscow not being invited.

"I believe that China could help us. That is why I would very much like to see certain proposals that the Chinese side has," Zelensky said.

"Ukraine has never said that China is our enemy," he added.

Asked whether he would consider China a friend, Zelensky said: "I believe that friends are those who help when things are difficult. And I would like China to be a friend to Ukraine."