Don't say his name - Trump is the Voldemort of G20 summit

For world leaders and diplomats at the G20 summit in Rio de Janeiro, US President-elect Donald Trump was the man who cannot be named.

Almost nobody would mention the next occupant of the White House directly, even as his impending return to power hung over the meeting.

Leaders would instead talk in coded terms about the "next administration," "turbulence" and "change."

But it was clear what they meant, even as they sought to avoid falling out with the man who will be at work in the Oval Office from January 20.

French President Emmanuel Macron, who expended considerable effort trying to win over Trump during the American's first term, made veiled comments at the summit about tariffs and climate.

"Any fragmentation or fracturing of the international order by tariff policies which are carried out by the strongest simply leads all others not to respect it," Macron said -- without referring to Trump by name.

Trump has pledged to impose sweeping tariffs on imports into the United States, including on goods from Europe and as much as 60 percent on goods from China.

Macron also referred to "fragile" climate policies, with Trump threatening to take the United States back out of the Paris accords that are aimed at reducing global warming.

- Swerve -

It was the same whenever leaders spoke, as they seemingly treated Trump like the villain Voldemort in the Harry Potter films and books, whose name the heroes cannot mention.

UN chief Antonio Guterres swerved any head-on mention of Trump when he talked of the "very important" U.S. role on climate and how he was "deeply confident" that America would "move in the direction of climate action."

The only places Trump's face could be seen were on placards held by protesters outside the summit venue -- and on the social media feed of Argentina's right-wing, Trump-supporting president.

Javier Milei reposted a meme contrasting a photo of himself meeting the smiling Trump at his Mar-a-Lago resort after the election, with another of Milei beside a grim-faced Brazilian President Luiz Inacio Lula da Silva.

Behind the scenes, officials were circumspect.

One European diplomat said that the continent had "worked with him before" and would do so again.

- 'Decisions' -

US officials insisted time and again that Trump's name did not come up in outgoing President Joe Biden's final meetings with his counterparts, or even that it was a major consideration.

"I don’t think we are expecting some major reorientation of how other countries look at the world or look at their relationship with us," Deputy National Security Advisor Jon Finer told reporters.

"They will make those decisions for themselves based on their interests, in January."

Perhaps it was partly out of deference to Biden, making his swan song on the international stage.

Biden himself skirted round the issue -- in fact he has long resisted mentioning the name of the man he often calls "my predecessor," who is now his successor.

The 81-year-old Biden tried to shore up his legacy while his fellow summiteers looked over his shoulder.

As Biden remarked that it was his final summit, he called for leaders to "keep going -- and I’m sure you will, regardless of my urging or not."

On the final day, Biden seemed to realize that the return of he-who-cannot-be named was nigh.

"I have much more to say," Biden said, before stopping himself and adding: "I'm not going to."