In a final communique issued at the end of a major two-day diplomatic summit in Switzerland, the vast majority of countries also backed a call for the full exchange of captured soldiers and return of deported Ukrainian children.

But not all attendees backed the document, with India, Saudi Arabia and the United Arab Emirates among those not included in a list of supporting states displayed on screens at the summit.

"We believe that reaching peace requires the involvement of and dialogue between all parties," the document stated.

It added: "We reaffirm our commitment to ... the principles of sovereignty, independence, and territorial integrity of all states, including Ukraine, within their internationally recognised borders."

More than 90 countries had gathered in the Swiss resort of Burgenstock for the summit, dedicated to discussing Kyiv's proposals for a route out of the conflict.

Moscow was not invited and has rejected the summit as "absurd" and pointless.

Kyiv had worked hard to secure attendance from countries that maintain warm relations with Russia.

The final document also called for all prisoners of war to be released in a "complete exchange" and for all Ukrainian children who had been "deported and unlawfully displaced" to be returned to Ukraine.

Kyiv accuses Russia of abducting almost 20,000 children from parts of the east and south of the country that its forces took control of.

Working groups at the summit also addressed the issues of global food security and nuclear safety.

"Food security must not be weaponised in any way," the declaration stated, adding that access to ports in the Black and Azov Seas was "critical" for global food supply.

And the countries also called for Ukraine to have "full sovereign control" over the Zaporizhzhia nuclear power plant.

Located in the south of Ukraine, the facility is Europe's largest nuclear energy site and has been controlled by Russian forces since early in the war.