Trump's tirade came just one day after French President Emmanuel Macron - once regarded as a close confidant of the U.S. president - rebuked Trump's "America First" brand of nationalism, comparing it to the forces that plunged Europe into conflict in the early 20th Century.
He also delivered a stinging indictment of nationalism, calling it "the exact opposite" of the patriotism shown by soldiers.
"By pursuing our own interests first, with no regard to others', we erase the very thing that a nation holds most precious, that which gives it life and makes it great: its moral values".
Trump arrived without his wife, Melania, who is visiting Versailles Sunday with Macron's wife, Brigitte Macron.
While Dr Merkel and Mr Macron are pushing back on America First, Mr Trump has a growing number of like-minded allies among Europe's leaders, including in Hungary, Italy and Poland, but they are as yet too few to set European policy.
Trump on Friday called Macron's comments "very insulting". He later described the commemoration as "very attractive". He said this decision was made in consultation with American officials. More than 1,500 Americans who perished in the war are buried there, the report states. "The whole world owes this moment of real joy to the heroes who are not here to help enjoy it". "They had arrived a few minutes late, missing the exact moment - 11 a.m. on November 11, 1918 - that four years of fighting ended", the Associated Press reported.
Rispal also said Trudeau's appearance at the Arc de Triomphe ceremony would be a reminder of Canada's contributions during the war, which aren't always recognized in Europe. She had slogans, including the words "Fake" and "Peace", written on her chest. The Femen group claimed responsibility.
Putin told Russia's RT network after the ceremony that he and Trump might have a conversation during the leaders' luncheon, but a formal meeting would wait until they cross paths at the G-20 Summit in Buenos Aries later this month.
At the forum German Chancellor Angela Merkel warned against taking peace for granted, saying, "We have to work for it".
Overhead, fighter jets ripped through the sky, trailing red, white and blue smoke.
California officials start grim search for the dead in blackened ruins
Studies have said wildfires often start due to extremely dry conditions, such as droughts that are spurred by climate change . Right now, families are in mourning, thousands have lost homes, and a quarter-million Americans have been forced to flee.
Those countries lost tens of thousands of soldiers far away in Europe and, most memorably in the brutal 1915 battle of Gallipoli, in Turkey. Britain had 880,000 military dead in the war.
In the afternoon, Trump travelled to the Suresnes American Cemetery just west of Paris to speak to veterans. "Will today be a symbol of lasting peace or a last moment of unity before the world falls into more disorder?" Macron asked. "It depends only on us".
They heard high-school students recalling the joy felt by soldiers and civilians alike when the fighting finally stopped at 11:00am on November 11, 1918.
The "America First" leader, who faced criticism on Saturday for cancelling a trip to an American cemetery because of rainy weather, will snub the Peace Forum.
In the four years of fighting, remembered for brutal trench warfare and the first use of gas, France, the British empire, Russian Federation and the United States had the main armies opposing a German-led coalition that also included the Austro-Hungarian and Ottoman empires.
The Great War killed 10 million soldiers and left millions of women widowed and children orphaned.
He explained that the USA would like to assist Europe with its security obligations, so long as the costs are reasonably distributed, and that's why he's pushed so aggressively for America's allies to increase their contributions to the North Atlantic Treaty Organization. Its role as host of the main global commemoration highlighted the point that the world mustn't stumble into war again, as it did so quickly and catastrophically with World War II.
When the war ended, the United States armed forces was on the cusp of becoming the major military power in the world.
President Donald Trump and Russia's Vladimir Putin have greeted one another at a ceremony in Paris marking the 100th anniversary of the end of World War I.