World leaders gather in Paris to mark 100th anniversary of WWI armistice

World leaders gathered in Paris will lead global commemorations on Sunday to mark 100 years since the end of World War I at a time of growing nationalism and diplomatic tensions.

Around 70 leaders including US and Russian Presidents Donald Trump and Vladimir Putin will mark the centenary of the 1918 Armistice in the French capital.

British Prime Minister Theresa May and Queen Elizabeth will attend a separate event in London, while New Zealand and Australia are holding their own ceremonies.

The Paris commemorations, centred on the Tomb of the Unknown Soldier beneath the Arc de Triomphe, are set to feature warnings about the modern-day danger of nationalism.

"This day is not just about remembering, but should be about a call to action," German Chancellor Angela Merkel said Saturday after visiting the forest clearing in eastern France where the Armistice was signed.

Merkel will give the opening address alongside UN Secretary General Antonio Guterres at a conference called the Paris Peace Forum which will take place after a memorial service on the Champs-Elysees on Sunday morning. Conceived by French President Emmanuel Macron, the Forum is intended to highlight the importance of international institutions in helping resolve conflicts, avert wars and spread prosperity.