By Steve Kingstone
BBC News, Rio de Janeiro
Representatives of the G20 group of developing countries have called for the resumption of global trade talks, which were suspended in July.
WTO head Pascal Lamy is at the Rio meeting
The G20, which consists of governments from Africa, Asia and Latin America, is meeting in the Brazilian city of Rio de Janeiro.
G20 officials will meet trade negotiators from Japan, the United States and the European Union.
World trade talks broke down amid ongoing disagreements over agriculture.
The Doha round of talks at the World Trade Organisation (WTO) was intended to favour poorer nations.
With the talks on hold, the developing world is leading the push to get them restarted.
Opening this meeting the Brazilian foreign minister, Celso Amorim, said failure was not an option. In a statement, the G20 called for the prompt resumption of official WTO talks, demanding that wealthier countries take the lead.
In practice, that means concessions on agriculture from both the United States and the European Union.
The EU protects its farmers from competition through steep import tariffs, while the US government pays around twenty billion dollars a year in farm subsidies.
On Sunday the G20 will hold separate meetings with chief negotiators from the EU, the United States and Japan.
With the head of the WTO, Pascal Lamy, also here, the meeting brings together almost all the key players.
No major breakthrough is expected before November's congressional elections in the US but if the Doha round is to succeed, talk must resume very soon after that.
The looming political deadline is July next year, when President Bush will lose his current authority from Congress to negotiate trade deals.