The American President turned on his French counterpart within 24 hours of returning from a World War One Armistice service in Paris.
He tweeted: “Emmanuel Macron suggests building its own army to protect Europe against the US, China and Russia.
“But it was Germany in World Wars One & Two — how did that work out for France? They were starting to learn German in Paris before the US came along.
Pay for NATO or not!”
Mr Trump described Mr Macron’s suggestion of a European army as “very insulting”.
Macron had said: “We have to protect ourselves with respect to China, Russia and even the United States of America.”
It was believed that Macron was lamenting the US decision to withdraw from a treaty with Russia that prohibited the manufacture of intermediate range nuclear missiles.
He was also angered by the French leader’s rebuke of nationalism — saying it is the opposite of patriotism — and said: “The problem is that Emmanuel suffers from a very low approval rating.
“There is no country more nationalist than France. Very proud people and rightfully so — make France Great Again!”
Trump appeared sullen during his 44-hour trip to Paris – cancelling an event to honour American troops at a cemetery because of bad weather.
His Twitter attack was evidence his close friendship with Macron – 32 years his junior - was over.
The two men have found themselves at odds on climate change, trade and Iran.
Mr Macron’s office declined to comment.