RIO DE JANEIRO (AP) — Brazil urged joint action Monday to alleviate hunger as the country hosted a summit of the Group of 20 leading economies amid global uncertainty over two major wars and the incoming U.S. president Donald Trump.

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Brazilian President Luiz Inácio Lula da Silva welcomed foreign leaders to Rio de Janeiro’s Museum of Modern Art on Monday morning and delivered an opening speech aimed at combating food insecurity.

“It is up to those of us here, around this table, to face the undelayed task of putting an end to this stain that shames humanity,” Lula told his colleagues. “That will be our greatest legacy.”

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Increased global tensions and uncertainty about an incoming Trump administration ahead of the summit had already dampened expectations for a strongly worded statement on the conflicts in the Middle East and between Russia and Ukraine. Further clouding the outlook, G20 officials told the Associated Press that Argentine negotiators have begun to dispute some of the draft language.

That has led experts to anticipate a final document focusing on social issues such as eradicating hunger – one of Brazil’s priorities – even though the intention is still to include at least a mention of the ongoing wars to take.

“Brazilian diplomacy is strongly committed to this task, but to expect a substantially strong and consensual declaration in a year like 2024 with two serious international conflicts is setting the bar very high,” said Cristiane Lucena Carneiro, professor of international relations at the University from Sao Paulo.

After Lulath rejected far-right former President Jair Bolsonaro’s 2022 re-election bid, there was some excitement in the international community at the prospect of the left-wing leader and shrewd diplomat hosting the G20. Bolsonaro had little interest in international summits, let ideology guide foreign policy and clashed with several leaders, including French President Emmanuel Macron. Lula took office often quoting the slogan: “Brazil is back.”

Under Lula, Brazil has returned to its decades-old principle of non-alignment to chart a policy that best protects its interests in an increasingly multipolar world, even as his government’s foreign policy has sometimes raised eyebrows .

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Two officials from Brazil and one from another G20 country say Argentine negotiators are standing in the way of a joint statement. They spoke on condition of anonymity because they were not authorized to speak publicly. Two of them said Argentine negotiators raised several objections to the draft, with the most vehement opponents of a clause calling for a global tax on the super-rich – which they had previously accepted in July – and another that promotes gender equality.

Last month, only Argentina opposed a G20 working group statement on women’s empowerment, preventing consensus. As Lula welcomed heads of state with smiles and warm hugs on Monday, he and Argentina’s right-wing President Javier Milei stood at arm’s length as they briefly shook hands. Milei is an avid Trump supporter.

Trump’s victory in the US presidential election earlier this month and the looming return of the “America First” doctrine could also hamper the diplomatic spirit needed for broad agreement on divisive issues, analysts said.

Ambassador Mauricio Lyrio, Brazil’s chief negotiator at the G20, told reporters earlier this month that Lula’s launch of a global alliance against hunger and poverty on Monday is as important as the final declaration. By Monday, 82 countries had signed the plan, the Brazilian government said. It is also supported by organizations such as the Rockefeller Foundation and the Bill & Melinda Gates Foundation.

At a demonstration Sunday on Rio’s Copacabana Beach, 733 empty plates were seen scattered across the sand, representing the 733 million people who would go hungry in 2023, according to United Nations data. Leaders were called on to take action.

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“Brazil wanted a global agreement to fight poverty, a project to finance the green transition and some consensus on a global tax on the super-rich. Only the first survived,” said Thomas Traumann, a former minister and political adviser based in Rio.

Be that as it may, at the start of the leaders’ afternoon session, Lula reiterated his call for a tax on billionaires.

“A 2% tax on the total wealth of super-rich individuals could raise approximately $250 billion per year, which could be invested in addressing social and environmental challenges around the world,” Lula said.

US President Joe Biden attended the summit after a stop in Lima for the Asia-Pacific Economic Cooperation forum. He also traveled this weekend to Manaus, a city in Brazil’s Amazon rainforest. It was the first time that a sitting American president set foot in the Amazon region.

The White House on Sunday announced a $50 million contribution to the Amazon Fund, the premier international collaborative effort to preserve the rainforest, following an earlier $50 million contribution. The Biden administration announced plans last year to donate $500 million.

White House officials have said Biden would also use the summits to urge allies not to lose sight of the end of the wars in Lebanon and Gaza and to maintain support for Ukraine as the country tries to repel Russia’s invasion. News emerged Monday of Biden’s decision to ease restrictions on Ukraine’s use of longer-range U.S. missiles to allow that country’s military to strike deeper into Russia.

During the summit, Biden highlighted his soon-to-end administration’s efforts on world hunger and poverty. He urged his colleagues to redouble efforts to alleviate these ills, and to resolve wars in Sudan, Gaza and Ukraine.

“The United States strongly supports the sovereignty and territorial integrity of Ukraine. I think everyone around this table should do the same,” Biden said.

Biden had planned to be part of the G20 group photo, a regular feature at most international summits, but that happened ahead of schedule, said a senior administration official, who was not authorized to comment publicly. He missed it, along with Canada’s Justin Trudeau and Italy’s Giorgia Meloni.

Any commitments Biden makes at the G20 could be overturned by the next White House administration. Trump’s election may also cause some countries to view China as a more reliable partner. British Prime Minister Keir Starmer met with China’s Xi Jinping on Monday, the first meeting between British and Chinese leaders since 2018, in a bid to mend ties with Beijing.

Russian President Vladimir Putin is the most notable absentee from the summit. The International Criminal Court has issued a warrant requiring member states to arrest him. Russian Foreign Minister Sergey Lavrov attended the meeting.

In a square a few blocks away, hundreds of demonstrators gathered to denounce the killings in Gaza, some beating drums and chanting: “Long live the struggle of the Palestinian people!” Among them were two rabbis who traveled from New York. Israel is not a member of the G20.

“We are trying to get the message across to the G20, to the leaders of the world,” said Rabbi Yisroel Dovid Weiss of the Neturei Karta International movement. “It’s so crucial. We are witnessing the mass murder of people and it is being perpetuated in the name of my religion, Judaism. We cannot be silent, we dare not remain silent.”

Aamer Madhani in Rio de Janeiro, Gabriela Sá Pessoa in Sao Paulo and Jill Lawless in London contributed to this report.