GENEVA - Peace conference on Ukraine ended on Sunday in Burgenstock, Switzerland, with some attendees failing to sign the joint communique.

It is essential to emphasize that any critical process will need Russia's participation.

Faisal bin Farhan Al Saud,  Saudi Arabian Foreign Minister 

According to the signatory list, those who did not sign the final communique include Armenia, Bahrain, India, Indonesia, Saudi Arabia, South Africa, among others.

Saudi Arabian Foreign Minister Faisal bin Farhan Al Saud said at Saturday's meeting that "it is essential to emphasize that any critical process will need Russia's participation."

Switzerland hosted the conference. Swiss Foreign Minister Ignazio Cassis also mentioned at a press conference on Sunday that most of the decisions made by this conference cannot be implemented without Russian participation.

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With Reuters inputs, over 90 countries attended the two-day talks at a Swiss Alpine resort even though Moscow was not invited.

Brazil attended only as an "observer".

Leaders including US Vice-President Kamala Harris, German Chancellor Olaf Scholz and French President Emmanuel Macron gathered at the mountaintop resort of Buergenstock. US President Joe Biden, in Europe for other events last week, did not attend. As Sunday's talks turned towards issues of food security and nuclear power, some leaders left early.

In her closing remarks, Swiss President Viola Amherd warned that the "road ahead is long and challenging".

No country came forward to host another such meeting, with notable silence from Saudi Arabia, mooted as a possible future venue. Foreign Minister Prince Faisal bin Farhan Al Saud said the kingdom was ready to assist the peace process but a viable settlement would hinge on "difficult compromise."

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"None of the participants in the 'peace forum' knows what he is doing there and what his role is," said Dmitry Medvedev, Russia's former president and now deputy chairman of the country's Security Council.