European Council President Donald Tusk warned that this may be one of the last chances "to restore our political community."
Speaking at a press conference, Tusk said this year's meeting will be "a difficult test of the unity and solidarity of the free world and its leaders."
French President Emmanuel Macron, who is hosting the summit in the resort town of Biarritz, said one of his main objectives is to "convince all our partners that tensions, especially trade tensions, are bad for everyone."
Thousands of people gathered in the nearby town of Hendaye to protest against the economic and environmental policies, urging world leaders to take action on climate change and other issues.
Trump ramps up trade disputeUS President Donald Trump, one of the main players at the center of those tensions, arrived with his wife Melania in the afternoon. He and other leaders were due to be officially greeted by Macron later on in the evening.
Shortly before leaving, Trump again threatened levying new taxes on French wine over its digital tax on big tech companies. Tusk responded by saying that the European Union is prepared to "respond in kind" should the US president make good on this threat.
The ongoing trade war between the US and China escalated shortly before the summit, after Trump raised tariffs. The US-China trade dispute is believed to be a major factor in the current global slowdown, raising concerns about a possible recession.
Macron urges action on Amazon firesThe massive, ongoing fires in the Amazon rainforest are also topping the agenda this year, with Macron threatening to withhold an EU trade agreement if Brazilian President Jair Bolsonaro does not take action.
The G7 will launch "not just an appeal, but a mobilization of all the powers there, but in partnership with the countries of Amazonia," to fight fires and invest in reforestation," Macron said.
German Chancellor Angela Merkel said that she supports discussing the fires during the summit, but disagrees that blocking the Mercosur trade deal with South American countries would reduce the destruction of the rainforest in Brazil.
"We will work on how we can help and support and send a clear message that everything must be done to stop the rainforest from burning," the chancellor said in a video message.
rs/aw (AP, AFP, dpa, Reuters)
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