The leaders of countries representing four-fifths of the global economy opened a two-day meeting in Argentina facing the deepest fractures since the first G20 summit convened 10 years ago in the throes of financial crisis.
"If we continue along the current course, the economic risks will increase, with potential effects for growth, jobs and consumer prices around the world", WTO Director General Roberto Azevedo said last week.
"We therefore support the necessary reform of the [World Trade Organization] to improve its functioning", the document says.
Prime Minister Lee Hsien Loong is attending the summit as Argentina has invited Singapore as chairman of Asean this year.
A White House spokeswoman denied this and Trump said on Friday the ships' seizure was the "sole reason" he scratched the meeting.
The wording on climate change was "a little bit more than the status quo but not backtracking", one European Union official said.
All eyes will be on a planned meeting between Trump and Chinese President Xi Jinping on Saturday to see whether they can find a way to calm the waters and make progress toward resolving differences that threaten the global economy.
Although the new pact inherits key features from the old one, Trump has declared it a victory for the USA workers he claims were cheated by Nafta and yesterday called it the most "modern and balanced agreement in history".
With Trump feuding with close USA allies, not least on climate change, two major summits this year ended without once-routine statements - those of the Group of Seven democracies and the Asia-Pacific Economic Cooperation forum.
With a rise in nationalist sentiment in many countries, the G20 - which accounts for two-thirds of the global population - faces questions over its ability to deal with trade tensions, which have roiled global markets, and ease geo-political disputes.
As world leaders flocked into the summit room to take their seats, Mohammad bin Salman and Russian President Vladimir Putin embraced each other with a friendly and enthusiastic high-five-shake and big smiles. "They are not focusing on the people who have needs", barber Ariel Villegas, 47, said at one protest Thursday outside the Argentine Congress building.
Saudi Arabia has insisted the prince had no prior knowledge of the killing.
US stands apart as G-20 summit stumbles on trade, climate
After the meeting, the PMO tweeted that the two leaders held productive discussions.
The U.S. leader was coy on Friday even as he noted some positive signs. But enough has been tweaked for Trump to declare victory on behalf of the United States workers he claims were cheated by NAFTA. "He's a good friend but we have a little bit of a dispute", Mr. Trump said about Xi in an interview with Voice of America on Friday.
"I think I understood you better in your language than I did on this".
"The fact that this is an agreement in three languages adds to the level of technical complexity, and it is on that level that we're just being sure that all the i's are dotted and all the t's are crossed".
Perhaps surprisingly, one country that was seen as particularly constructive was Russian Federation, the officials said.
The officials weren't authorized to be named speaking about the closed-door discussions and spoke on condition of anonymity.
The US has hit a total of $250bn (£196bn) of Chinese goods with tariffs since July, and China has retaliated by imposing duties on $110bn of US products.
China, in response, is threatening to impose taxes on an additional 5,000 types of American imports worth about $60 billion. China calls the United States protectionist and has resisted what it views as attempts to intimidate it.
China, which has already slapped tariffs on US$110 billion in United States goods, is likely to retaliate, ramping up a conflict that has already rattled financial markets and caused forecasters to downgrade the outlook for global economic growth.
If that was created to soothe Trump, Xi more generally urged his fellow G20 leaders "to stick to openness" and to "steer (the) world economy responsibly", Xinhua reported.
A final communique adopted after all-night haggling in the summit in Argentina said all other G20 members agreed to implement the "irreversible" Paris Agreement on climate change, while respecting different paces of economic development.
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