EU Council President Donald Tusk warned Saturday that US President Donald Trump's escalating trade skirmishes with China and Europe could force economies around the world into recession.
"Trade wars will lead to recession, while trade deals will boost the economy," Tusk said as leaders of the Group of Seven (G7) countries descended on the French resort town of Biarritz for a three-day summit.
French President Emmanuel Macron, the summit's host, also warned of the widespread fallout from the trade disputes.
In a televised address to the nation from Biarritz, Macron said his goal was "to convince all our partners that trade tensions are bad for everyone".
And he vowed to work on "a real recovery" for the global economy.
"We have to achieve some form of de-escalation, stabilise things, and avoid this trade war that is taking place all over," he said.
"We have to work for more growth, and more jobs," he added.
France in particular was targeted by Trump just before his departure for Biarritz, when the US leader again threatened to impose heavy tariffs on French wines in retaliation for a new French tax on large US tech companies like Google.
"Frankly, I don't want France going out and taxing our companies. Very unfair," he told reporters in Washington on Friday.
"If they do that, we'll be taxing their wine or doing something else. We'll be taxing their wine like they've never seen before," he said.
The trade disputes have jumped to the forefront of this year's G7 summit, with both Tusk and Macron also warning that an ambitious deal in the works between the EU and South American nations is now at risk over Brazil's response to an outbreak of wildfires in the Amazon.
"It is hard to imagine a harmonious process of ratification by the European countries as long as the Brazilian government allows for the destruction of the green lungs of planet Earth," he added.
Tusk added that the EU was ready to offer financial help to fight the fires.