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Donald Trump and France’s Emmanuel Macron have both said Europe should pay more of its defence costs, a day after the US president lambasted the idea of a European army.
Mr Trump is in Paris ahead of events marking the end of World War One.
He said the US wanted “a strong Europe,” but the defence bill “has been largely on the United States.”
Mr Macron said he agreed that “we need a much better burden-sharing within Nato” – the US-led alliance.
“When President Trump has to protect one of the states of the United States he doesn’t ask France or Germany or another country to finance. That’s why I do believe that we need more investments,” he said.
Around 70 world leaders are gathering in Paris for events marking the Armistice that ended World War One, which was signed 100 years ago this Sunday.
The Trump-Macron show of unity came despite earlier tensions, triggered when the French leader said the EU needed a joint army to handle threats from the US, China and Russia.
“We have to protect ourselves with respect to China, Russia and even the United States of America,” he told French radio station Europe 1 on Tuesday.
“I want to build a real security dialogue with Russia, which is a country I respect, a European country – but we must have a Europe that can defend itself on its own without relying only on the United States.”
Mr Trump responded angrily in a Friday night tweet, writing: “President Macron of France has just suggested that Europe build its own military in order to protect itself from the US, China and Russia. Very insulting, but perhaps Europe should first pay its fair share of NATO, which the US subsidizes greatly!”
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Mr Macron has already raised defence spending considerably to meet Nato target of 2% of the GDP going to defence.
He is also overseeing the formation of a European rapid reaction force, a nine-nation endeavour much smaller than an actual army, which is backed by Germany and the UK.
What’s the plan for Armistice Day?
After an hour of talks, Mr Trump and Mr Macron were set to be joined by their wives Melania and Brigitte for lunch.
On Saturday afternoon, Mr Macron will meet Germany’s Chancellor Angela Merkel in the town of Compiegne in northern France, where the Allies and Germany signed the Armistice.
Visiting heads of state will then gather for dinner in Paris in the evening.
Donald Trump had been scheduled to visit two American cemeteries over the weekend, but later cancelled his trip to Ainse-Marne American Cemetery and Memorial due to “scheduling and logistical difficulties caused by the weather”.
Gen John Kelly, the White House Chief of Staff, will attend on his behalf.
Mr Trump is still expected to attend a sombre commemoration at the Tomb of the Unknown Soldier, a memorial to France’s fallen under the Arc de Triomphe in Paris.
Tweeting early on Saturday morning, he remarked: “Is there anything better to celebrate than the end of a war, in particular that one, which was one of the bloodiest and worst of all time?”
I am in Paris getting ready to celebrate the end of World War One. Is there anything better to celebrate than the end of a war, in particular that one, which was one of the bloodiest and worst of all time?
— Donald J. Trump (@realDonaldTrump) November 10, 2018
Sunday afternoon will see Mr Macron and Mrs Merkel attend a peace conference – the Paris Peace Forum – with leaders including Mr Putin and Turkey’s Recep Tayyip Erdogan.
Mr Trump will not be present, however, which his National Security Advisor John Bolton put down to a diary full of “pressing issues”.
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Will Trump meet Putin?
The status of this proposed meeting has changed repeatedly in recent weeks.
On Wednesday the Kremlin said the pair would hold a “short working lunch” at the Élysée Palace in Paris, but the US contradicted that the same day.
“I don’t think we have anything scheduled in Paris and I’m coming back very quickly,” the president said. “I don’t think we have time set aside for that meeting.”
The two men may meet at a lunch for world leaders on Sunday, but it remains to be seen if a more formal discussion will ultimately materialise.