Squabbles erupted among G7 nations on Saturday even before their leaders had gathered for an annual summit, exposing sharp differences on global trade tensions, Britain's exit from the EU and how to respond to the fires raging in the Amazon rainforest.
French President Emmanuel Macron, the summit host, planned the three-day meeting in the Atlantic seaside resort of Biarritz as a chance to unite a group of wealthy countries that has struggled in recent years to speak with one voice.
Macron set an agenda for the group - France, Britain, Canada, Germany, Italy, Japan and the United States - that included the defense of democracy, gender equality, education and the environment. He invited Asian, African and Latin American leaders to join them for a global push on these issues.
However, in a bleak assessment of relations between once-close allies, European Council President Donald Tusk said it was getting "increasingly" hard to find common ground.
"This is another G7 summit which will be a difficult test of unity and solidarity of the free world and its leaders," he told reporters ahead of the meeting. "This may be the last moment to restore our political community."
US President Donald Trump brought last year's G7 summit to an acrimonious end, walking out early from the gathering in Canada and rejecting the final communique.
Trump arrived in France a day after lashing back at a new round of Chinese tariffs by announcing Washington would impose an additional 5 percent duty on some US$550 billion worth of Chinese imports, the latest tit-for-tat trade war escalation by the world's two largest economies.
"So far so good," Trump told reporters as he sat for lunch on a seafront terrace with Macron, saying the two leaders had a special relationship. "We'll accomplish a lot this weekend."
Macron listed foreign policy issues the two would address, including Libya, Syria and North Korea, adding that they shared the objective of preventing Iran from obtaining nuclear weapons.
However, the initial smiles could not disguise their opposing approaches to many problems, including the knotty question of protectionism and tax.
Before his arrival, Trump repeated a threat to tax French wines in retaliation for a new French levy on digital services, which he says unfairly targets US companies.
Two US officials said the Trump delegation was also irked that Macron had skewed the focus of the G7 meeting to "niche issues" at the expense of the global economy, which many leaders worry is slowing sharply and at risk of slipping into recession.
French riot police briefly used water cannons and tear gas on Saturday to disperse anti-capitalism protesters in Bayonne, near Biarritz.
A police helicopter circled overhead as dozens of protesters, some wearing face masks, taunted lines of police.
'Money for the rich'
Anti-summit protests have become common, and on Saturday thousands of anti-globalisation activists, Basque separatists and "yellow vest" protesters marched peacefully across France's border with Spain to demand action from the leaders.
"It's more money for the rich and nothing for the poor. We see the Amazonian forests burning and the Arctic melting," said Alain Missana, an electrician wearing a yellow vest - symbol of anti-government protests that have rattled France for months.
EU leaders piled pressure on Friday on Brazilian President Jair Bolsonaro over fires raging in the Amazon rainforest.
- Brazil tribe vows to fight deforestation until the 'last drop of blood'
- Brazil likely to send the army to fight the fires
- Scientists blame 'corrupt governments and corporate interests'
Macron said Bolsonaro had lied in playing down concerns about climate change at a G20 summit in Japan in June, and threatened to veto a trade pact between the European Union and the Mercosur bloc of South American countries.
The UK's Johnson has voiced deep concern about the forest blazes, but appeared to disagree with Macron on how to respond.
"There are all sorts of people who will take any excuse at all to interfere with trade and to frustrate trade deals and I don't want to see that," he said.