Donald Trump has described Emmanuel Macron's call for an EU army to protect itself from the US as "very insulting".
The US president touched down in Paris on Friday evening ahead of a weekend of events commemorating the end of the First World War but did not take long to hit out at his French counterpart.
Mr Trump tweeted a response to an idea floated by Mr Macron for the European bloc to have its own dedicated military, designed to defend Europe from China, Russia and the US.
"President Macron of France has just suggested that Europe build its own military in order to protect itself from the US, China and Russia," Mr Trump wrote.
"Very insulting, but perhaps Europe should first pay its fair share of NATO, which the US subsidies greatly!"
President Macron of France has just suggested that Europe build its own military in order to protect itself from the U.S., China and Russia. Very insulting, but perhaps Europe should first pay its fair share of NATO, which the U.S. subsidizes greatly!
— Donald J. Trump (@realDonaldTrump) November 9, 2018
The two leaders are due to meet on Saturday for talks on topics expected to include European security, Syria and Iran.
Mr Macron made the pitch during an interview with radio station Europe 1 before a meeting of defence ministers from nine European countries to discuss how such a force would operate.
"We have to protect ourselves with respect to China, Russia and even the US," Mr Macron said.
"When I see President Trump announcing that he's quitting a major disarmament treaty which was formed after the 1980s Euromissile crisis that hit Europe, who is the main victim? Europe and its security.
"We will not protect the Europeans unless we decide to have a true European army.
"We need a Europe which defends itself better alone, without just depending on the US."
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Mr Trump has repeatedly criticised the amount of money European nations commit to NATO compared to the US.
Earlier this year, during a private meeting with NATO leaders in Brussels, he suggested allies double their targeted 2024 spending commitment from 2% of their GDP to 4%.