Ministers meeting for the Summit of South American-Arab Countries, expected to open on Tuesday, will focus on ways to boost economic ties.
On Monday, Arab foreign ministers held a preparatory meeting prior to the summit opening.
The summit, which brings together leaders from countries resentful of Washington's hand in everything from "regime changes" to rampant globalisation, is also expected to be a platform for forging new political alliances.
But Aljazeera's Dima al-Khatib said only Djibouti, the Comoros Islands, Algeria, Iraq, Qatar and the Palestinian Authority are represented at the highest levels.
Only three more Arab prime ministers are expected to attend, although organisers are pleased with Iraq's presence as it is the first international engagement for the country's new president.
Al-Khatib added that Washington is annoyed with Latin America strengthening ties with China, Russia and the Arab world, and senior US officials said they are waiting to read about the summit's position on "terrorism" in particular.
Princeton University's Amany Jamal, a Middle East political development expert, said it is important for the summit countries to not be seen as being bullied by the West.
"What better way to do that than re-establish dominance on another front," he said.
Rubbing shoulders in Brasilia will be leaders ranging from Venezuelan President Hugo Chavez, a self-proclaimed revolutionary and outspoken US critic, to Palestinian leader Mahmoud Abbas, Algerian President Abdelaziz Bouteflika and the summit host, Brazilian President Luiz Inacio Lula da Silva.
The event is part of Silva's push to unite developing nations on issues such as reform of the United Nations Security Council and the elimination of rich nations' subsidies for agriculture.
On Monday, Silva is to meet privately with the prime ministers of Syria, Lebanon and with Abbas.
"It's important for these countries to not be seen as being bullied by the West. What better way to do that than re-establish dominance on another front"
Later, he will host a dinner for Chavez and Argentinian President Nestor Kirchner, who angered investors in developed countries this year by paying only 30% on the dollar on Argentina's mammoth $103 billion debt default.
The summit could also serve as an initial step towards negotiations for a free trade agreement between two regions currently doing little business together.
Brazilian officials said a summit declaration will focus on social issues such as Silva's push to eradicate worldwide hunger, but it is unclear how summit participants will address touchy issues such as terrorism and the Middle East peace process.
The meeting is billed as a step in so-called South-South cooperation to join the interests of poor countries so they have better negotiating power with rich nations that typically dominate global politics and trade negotiations.
South American countries are already moving forward quickly on that front by trying to boost political ties with Asia - particularly China - a major buyer of products ranging from Brazilian and Argentinian soy to Chilean copper.
The Middle East, however is Latin America's weakest regional trading partner.
Hugo Chavez has pushed for close
ties between developing nations
Brazil, South America's largest economy, exports just $4 billion annually to the Middle East and imports $4.1 billion, mostly in petroleum.
But shipments of products such as sugar, beef and chicken from Brazil to the Middle East are exploding.
The Arab-Brazilian Chamber of Commerce estimates Brazilian exports to Arab countries could double within five years.
South American markets
The summit gives the Arab nations the chance to explore ways to penetrate a largely untapped South American export market.
Exports to Latin America from regional economic powerhouse Egypt, for example, accounted for only 1% of the country's total exports in the first 11 months of 2004.
And the Arabs will get to see firsthand the progress South America has made in economic reforms - such as the privatisation of state industries and fiscal and political reforms that have boosted foreign investment.
"From the Arabs' perspective, Latin America is probably the best case to benchmark the pace of progress in the Arab world"
"From the Arabs' perspective, Latin America is probably the best case to benchmark the pace of progress in the Arab world," said Georgetown University political analyst Tarik Youssef.
Brazilian media stressed on Sunday that the leaders of key US allies such as Egypt and Saudi Arabia will be noticeably absent. But Iraqi President Jalal Talabani is scheduled to attend.
A US request to officially observe the event was denied, but Chile's ambassador to Brazil, Oswaldo Puccio, said the move should not be seen as a sign of opposition to the US.