When the two men met on Monday in New York, they shook hands lightly and got down to the tasks at hand.

They agreed to disagree on the Iranian nuclear accord and Trump's protectionist policies and one-sided support for Israel, according to two French presidential advisers.

The businesslike mood contrasted with Trump's fawning over Macron at a state dinner in April, and Macron's lavish Eiffel Tower welcome for the Trumps last year.

Hours after their meeting, the two men laid out starkly different world views in speeches at the UN General Assembly.

"Nationalism always leads to defeat," said the progressive, multilateralist Macron.

"We reject the ideology of globalism and we embrace the doctrine of patriotism," said Trump, trumpeting his America-first, zero-sum vision.

Macron later ticked off ways Trump has disappointed him - from his withdrawal from the Paris climate accord and Iranian nuclear deal to unilateral tariffs on steel and aluminium.

Still, Macron said he'll keep working with Trump on a "case by case" basis, and insisted that they're not rivals but pragmatic allies.

At their meeting "both leaders reaffirmed their commitment to closely coordinate to address global challenges," the White House said.

Macron specified that meant working together on Syria and a new US trade deal with Europe - as long as it doesn't involve such things as American GMO products that make European consumers wary.

Macron appeared to convince Trump to follow through on promises to visit Paris in November to mark 100 years since the armistice ending World War I, and added a possible battlefield tour to Trump's program.

And Trump offered Macron an unexpected compliment, praising him as the new "hardliner" of Europe for his tough stance on Brexit negotiations, according to the French officials.

Given Trump's combative, mercurial presidency, the French aides made a point to stress one positive thing about Trump and Macron's latest sit-down session: no new conflicts emerged.

Australian Associated Press