Around 11 a.m. local time (1000 GMT), Macron and delegates from around 70 countries walked side by side towards the Arc de Triomphe to pay tribute to around 10 million soldiers killed during the 1914-1918 war.
When asked by journalists whether he had a chance to talk to Trump, Putin said "yes", Interfax and RT reported.
Trump took umbrage at a recent interview in which Macron talked about the need for a European army and listed the United States along with Russian Federation and China as a threat to national security.
"I would say I'm a patriot".
Also traveling on his own was Russian President Vladimir Putin, who shook Trump's hand, flashed him a thumbs-up sign and patted Trump's arm as he arrived.
It also underlined growing concerns over the reliability of USA security guarantees under Trump, and his wider commitment to a postwar global order the US was largely responsible for building and has benefited from, including economically.
The earlier show of unity at the Arc de Triomphe comes at a time of growing tensions between liberals and populists in the European Union, as well as between Europe and the U.S., two years into Trump's "America First" presidency.
An armistice marked the official end of World War I at exactly 11:00am, 100 years ago.
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Now enter the Camp Fire . "I know that a lot of you are feeling a lot of pain right now, and a lot of shock", she said. As of Sunday, it had burned 83,000 acres and at least 177 buildings and was 10 percent contained.
"The lesson of the Great War can not be that of resentment between peoples, nor should the past be forgotten", he said, alluding to the millions of women widowed and children orphaned by the conflict, as well as the 10 million soldiers killed.
Macron, sporting a cornflower in his lapel - the French equivalent to Britain's remembrance poppy - and Merkel reviewed grey-clad soldiers from the Franco-German brigade, before unveiling a plaque to Franco-German reconciliation.
Mr Tusk, an opponent of Poland's right-wing government, said the political disputes about Poland's future are "sometime too strong", but stressed that "our bond is much stronger and much more important, because it is you, Poland".
Earlier he visited a cemetery in Suresnes in western Paris, saying he had gone there "to pay tribute to fearless Americans" who died in the war. He pulled out of a similar ceremony east of Paris on Saturday due to the weather. "They have a word, it sort of became old fashioned, it's called a nationalist...you know what I am, I'm a nationalist". "We renew our sacred obligation to memorialize our fallen heroes" at the cemetery, "where they rest for all eternity", he said.
US President Donald Trump, whose hardline nationalism has badly shaken the Western alliance, arrived in Paris criticising host Macron for being 'insulting'.
The Veterans Day speech came a day after Mr. Trump was criticized for failing to visit a different American cemetery about 60 miles outside of Paris Saturday because rain grounded the helicopter he had planned to take.
Trump delivered the speech as other leaders were gathered for the Paris Peace Forum, which aims to revive collective governance and worldwide cooperation to tackle global challenges.
They turned the tide of the war. Trump is scheduled to visit another military cemetery before departing Sunday.
United Nations chief Antonio Guterres meanwhile warned of "parallels" between the present day and the unstable and risky 1930s as he marked the centenary of World War I in a speech at the Paris forum.