Volodymyr Zelensky (centre) and world leaders pose for a family photo in Stansstad, Switzerland, on Saturday Reuters

World leaders gathered at a Swiss mountain resort on Saturday to try to build support for Ukraine's peace proposals at a summit skipped by US President Joe Biden, shunned by China and dismissed as a waste of time by Moscow.

More than 90 countries will take part, but China's absence in particular has dimmed hopes the summit would show Russia as globally isolated, while recent military reverses have put Kyiv on the back foot. The war in Gaza between Israel and Hamas has also diverted the world's attention from Ukraine.

The talks will focus on broader concerns triggered by the war, such as food and nuclear security.

Ukrainian President Volodymyr Zelenskiy has trumpeted the summit's wide attendance as a success and predicted "history being made", adding that agreements stemming from it will be part of the peacemaking process.

"Ukraine never wanted this war. It's a criminal and absolutely unprovoked aggression by Russia," he said alongside Swiss President Viola Amherd, who said the conflict had brought "unimaginable suffering" and violated international law.

German Chancellor Olaf Scholz called the gathering an important step to discuss peace and security questions.

Volodymyr Zelensky gestures during the Summit on peace in Ukraine in Stansstad, Switzerland, on Saturday. Reuters

"This is a small plant that needs to be watered, but of course also with the perspective that more can then come out of it," he told Welt TV.

Biden sent US Vice President Kamala Harris to represent him — riling Kyiv — while Saudi Arabian Crown Prince Mohammed Bin Salman will be represented by his foreign minister and India dispatched a lower-level delegation. Beijing is staying away after Russia was frozen out of proceedings.

Harris announced more than $1.5 billion in energy and humanitarian aid for Ukraine, where infrastructure has been pounded by Russian airstrikes since the 2022 invasion.

"This war remains an utter failure for (Russian President Vladimir) Putin," Harris said during a meeting with Zelenskiy.

A military helicopter hovered over the luxury Buergenstock resort overlooking Lake Lucerne on Saturday as leaders arrived by helicopter on a patch of grassland fenced off with razor wire while cows grazed nearby.

Reuters