At their impromptu lunch on Saturday, Mr. Macron called Mr. Trump “a very special guest for us” and pledged cooperation. But for those around the American president, their meeting was just the first of what promised to be a series of fraught interactions as he presses his case with his counterparts.
And amid preparations for those top-level encounters, down the road in Bayonne, 13,000 police officers were arrayed, firing tear gas and water cannons on Saturday to disperse protests by demonstrators opposed to globalization and other tenets the Group of 7 represents.
For Mr. Trump’s first one-on-one meeting on Sunday morning, he has chosen to meet with Boris Johnson, the new British prime minister, who has been engaged in his own extended verbal spat with the Continent’s leaders over the terms of Britain’s exit from the European Union. Mr. Trump has publicly expressed support for Brexit, a position that has further irritated his already tense relationships on the world stage.
The president will meet with Shinzo Abe, the Japanese prime minister, later on Sunday amid reports that negotiators for the two countries have reached a deal in principle on tariffs. The men could formally sign a deal next month, a victory that is likely to please Mr. Trump, who has repeatedly praised his relationship with Mr. Abe.
His discussion with Mr. Trudeau on Sunday is likely to be far frostier, although by the time the seven world leaders had met Saturday for a working dinner at the base of a lighthouse built in the 1830s, Mr. Trump had so far resisted the temptation to criticize the Canadian prime minister.
Mr. Trump has shown less restraint when it comes to Angela Merkel, the departing chancellor of Germany, whom he will meet with on Monday. In a tweet on Wednesday, in a week of complaints about Federal Reserve policy, he lamented that Germany was paying “zero interest” on debt while the United States is “paying interest.”
That followed tweets in June, when Mr. Trump alleged that crime in Germany was “way up” and insisted that “people in Germany are turning against their leadership” because of decisions to let migrants into the country.