G20 powers geared for summit talks on Friday in a deserted Argentine capital, after an incident-packed buildup dominated by controversies pitting US President Donald Trump against Russia and his combative stance on trade and climate change.
With Buenos Aires on security lockdown, Trump along with the Russian and Chinese presidents were among the world leaders gathered against a backdrop of tensions surrounding also the Ukraine conflict and relations with Saudi Arabia.
On the G20 margins, Trump scored one victory for his "America First" agenda with the signing of a successor to the North American free trade pact NAFTA, the US-Mexico-Canada Agreement (USMCA).
Although the new pact inherits key features from the old one, Trump has declared it a victory for the US workers he claims were cheated by NAFTA and on Friday called it the most "modern and balanced agreement in history."
Macron on Thursday rejected those who wish to confront economic challenges by being "bellicose, isolationist and closing down borders."
With a major UN meeting on climate change starting next week in Poland straight after the G20, UN chief Antonio Guterres said in Buenos Aires that "this is a make-it-or-break-it moment."