French President Emmanuel Macron yesterday urged world leaders to reject "the law of the most powerful," offering a rebuke to Donald Trump's go-it-alone approach to global challenges.

Macron did not refer to the US president by name but his address to the UN General Assembly outlined positions that were polar opposites to Trump's world view.

"Some have chosen the law of the most powerful, but it cannot protect any people," said Macron, who reaffirmed his strong backing for multilateralism embodied by the United Nations and its global peace efforts.

Earlier at the UN podium, Trump vowed to "never surrender America's sovereignty to an unelected, unaccountable global bureaucracy" and to reject "the ideology of globalism."

Since Trump took office in 2017, the United States has ditched the Iran nuclear deal and the Paris climate deal -- two international accords that France has championed.

The US administration has cut funding to the United Nations, aid agencies and to UN peacekeeping missions.

Touching on the Israeli-Palestinian conflict, the French president said there was no credible alternative to the two-state solution that Trump has imperiled with his recognition of Jerusalem as Israel's capital.

Defending the Iran nuclear deal, Macron urged dialogue with Tehran, again clashing with the US president who a few hours earlier called on world governments to isolate Iran.

Speaking at a press conference, Macron said Iran should be able to sell oil to bring down prices, challenging Trump's plan to tighten an economic vise around Iran.