The World Trade Organization opened a conference Sunday under the cloud of US hostility to multilateral trade accords.
The 164-member WTO is also wracked by disagreements over China and has been struggling to kickstart stalled trade talks.
The Buenos Aires meeting, which lasts through Wednesday, is the first in the era of US President Donald Trump, who has pummeled the body relentlessly since taking office, describing it as a "disaster."
The Trump administration has made the WTO a preferred target of its "America First" policy, threatening to pull the US out of the trade organization it says is hampering its ability to compete.
Argentina's President Mauricio Macri said, in opening remarks, that "WTO problems get fixed with more WTO -- not with less WTO."
Trump has already withdrawn the United States from the Trans-Pacific Partnership (TPP) and insisted on renegotiating the North American Free Trade Agreement (NAFTA) with Mexico and Canada.
WTO Director-General Roberto Azevedo said Sunday he will ask US Trade Representative Robert Lighthizer for "political commitment, political will and flexibility."
"Without flexibility we will not get anywhere," Azevedo said at an opening press conference at a Buenos Aires hotel.
Washington has been blamed for blocking appointments of judges to the WTO's dispute settlement system, saying it was ineffective and insisting on a more aggressive approach to defending its interests.
The dispute body arbitrates international rows over subsidies or tariffs, among other things playing an important role in the standoff between US and European plane-makers Boeing and Airbus.
The European Union, on the other hand, comes to the conference with a robust spirit of multilateralism. The EU and Japan announced Friday that they have finalized a major trade agreement.
EU officials will also meet with counterparts from the South American trade bloc known as Mercosur to continue talks on a free trade accord. These discussions have been going on for nearly 20 years.
Expectations for any kind of a breakthrough at the Buenos Aires meeting are low.
For the past decade the WTO has failed to make progress in the so-called Doha Round of trade liberalization talks, which began in 2001.
The WTO is also accused of failing to do enough to resolve problems that some of its members have with China.
"There is life after Buenos Aires," said the president of the conference, Susana Malcorra of Argentina.
She has said a deal was likely to end harmful fisheries subsidies, of keen interest to developing countries.
Beijing, meantime, wants to be seen by the WTO as a "market economy," but the Europeans and the United States -- for once on the same wavelength on trade issues -- oppose this. Any such recognition would entitle China to preferential economic treatment under WTO rules.
It is currently classed as a non-market economy. That status allows the US and others to use a special recourse to levy anti-dumping duties against China if they determine that it is selling its goods -- notably steel and aluminum -- at unfairly low prices abroad.
A European diplomat in Buenos Aires said protectionist US rhetoric may actually give fuel to negotiations between the EU and Mercosur.