French President Emmanuel Macron and US President Donald Trump marked France's national day together at a military parade which showcased the warming relations between the two leaders.
Mr Macron invited Mr Trump to be his guest of honour at the Bastille Day celebration.
It featured French and US troops marching down the Champs-Elysees in Paris, opened to a flypast by two US F-22 stealth fighters and culminated with a roaring pass by French jets.
"Nothing will ever separate us," Mr Macron said during a speech at the end of parade, adding that Mr Trump's presence was "the sign of a friendship across the ages" between their countries.
The Paris parade this year marked the centenary of the US entering World War I in 1917 and featured 63 planes, 29 helicopters, 241 horses and 3,720 soldiers, including US troops dressed in the brown uniform and gaiters of the Great War.
Mr Trump tweeted that it was a great honour "to represent the United States at the magnificent #BastilleDay parade".
Before departing, the two leaders shared another long and muscular handshake between the men.
US President Trump and French President Macron just shared an awkwardly long handshake during Bastille Day celebrations in Paris pic.twitter.com/uyBo1FkknU
— RTÉ News (@rtenews) July 14, 2017
Mr Macron rolled out the red carpet for Mr Trump's two-day visit, hoping to improve relations and persuade the US president to change his mind about withdrawing from the global Paris agreement on climate change.
Mr Trump said cryptically after their talks yesterday that "something could happen with respect to the Paris accord ... but we will talk about that over the coming period of time".
Mr Trump had appeared isolated at a meeting of world leaders last weekend in Germany over his decision to withdraw the US from the Paris global climate change agreement and his protectionist stance on trade.
The warm body language between him and Mr Macron seemed at odds with broader concerns about the transatlantic relationship since Trump's election victory in November last year.
The two men enjoyed a "dinner between friends" last night at a Michelin-starred restaurant on the Eiffel Tower. US First Lady Melania Trump and France's First Lady Brigitte Macron were also in attendance.
US President Donald Trump greeted France's First lady Brigitte Macron by telling her "You're in such good shape". pic.twitter.com/aLNzhWeIow
— RTÉ News (@rtenews) July 14, 2017
Mr Trump also said yesterday that the bond between the US and France, as well as the friendship between him and Mr Macron, was "unbreakable".
Despite their differences on climate change and trade, the two leaders focused on their close cooperation on fighting the so-called Islamic State group in Syria and Iraq during their talks.
Bastille Day commemorates the storming of the Bastille prison in 1789 - the start of the French Revolution and a turning point in world history.
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For France, this year's holiday has an additional poignancy as the first anniversary of one of the deadliest Islamist militant attacks of the past few years.
After the parade, his first as President, Mr Macron will head for the Mediterranean city of Nice, where he will join a commemoration for the 86 people who died when a Tunisian man drove a truck at a crowd on the waterfront a year ago.
Terror attacks in France have killed more than 230 people since January 2015. Interior Minister Gerard Collomb says seven terror plots have been foiled since the start of this year.
