The leaders are holding three hours of talks at a 70th anniversary summit overshadowed by rows.
With U.S. President Donald Trump and French President Emmanuel Macron blowing hot and cold over NATO’s function, the 29-member military alliance is looking for reinvigoration as it marks the 70th anniversary of its Cold War-era founding.
“Clearly it is very important that the alliance stays together,” British Prime Minister Boris Johnson told reporters as he prepared to welcome heads of state and government. “But there is far, far more that unites us than divides us.”
Leaders held preliminary meetings in London on Tuesday, during which stark differences were aired, with Trump, who in the past has called NATO obsolete, criticising Macron for comments last month about NATO’s strategic “brain death”.
Trump said Macron’s remarks were “nasty”. He also described allies who spend too little on defence as “delinquent”.
Macron held his ground, saying as he arrived that it was important for leaders to discuss issues in an open and forthright manner if they were to find solutions.
“I think it’s our responsibility to raise differences that could be damaging and have a real strategic debate,” he said. “It has started, so I am satisfied.”
Earlier, in a message on Twitter, Macron was direct about the challenges NATO faces. “It is a burden we share: we can’t put money and pay the cost of our soldier’s lives without being clear on the fundamentals of what NATO should be,” he said.
In an illustration of the awkward mood, Macron, Johnson and the prime ministers of Canada and the Netherlands were caught on video at a Tuesday evening Buckingham Palace reception, apparently making light of Trump’s media appearances.
“It was like a 40-minute press conference,” Canada’s Justin Trudeau can be heard saying, with Queen Elizabeth’s daughter Princess Anne listening on. “I just watched his team’s jaws drop to the floor,” Trudeau added with a chuckle.