Luiz Inacio Lula da Silva's comments came on Monday before the talks scheduled to take place in Miami, Florida this week.
"If the poor nations want to be heard, they have to voice their interests," da Silva told delegates at a conference on ways to reach development goals set by the United Nations.
"It means taking the paradoxes of globalisation to the negotiating table."
Trade ministers are meeting in Miami this Thursday and Friday on the Free Trade Area of the Americas, a proposed trade agreement covering 34 countries stretching from Canada to Argentina.
"We defined a transparent agenda of our interests in FTAA talks with the United States", said Lula.
Latin America's largest country, Brazil has fought US efforts to include FTAA rules on investments, patents and services that would allow US business greater access to its medical, investment and technology markets.
Brazil has said it will not accept such rules while the US refuses negotiations on its domestic agricultural subsidies that defend US farmers from Brazil's farm exports.
The country is prepared to push in Miami for a trade agreement that gives developing countries' agricultural producers maximum access to lucrative US markets but defends the emerging industries in developing nations.
Lula said Latin America and the Caribbean were struggling to reach basic development targets, and while "the rich defended their fortune, the poor got poorer".
"... the rich defended their fortune, the poor got poorer"
Luiz Inacio Lula da Silva
Flanked by the presidents of Guyana and the Dominican Republic, Lula said Latin America did not want a repeat of the 1990's when so-called Washington Consensus economic policies failed to raise living standards for the region's poor.
Those policies urged nations to open their economies to global investment and trade but resulted in financial speculation and foreign capital dependence, Lula said.
He pointed out that in Latin America and the Caribbean the number of people earning less than a dollar a day had risen to 57 million compared with 48 million in 1990.
The Americas trade talks were launched in 1994 by leaders from every country in the Western Hemisphere, except Cuba, with an eye toward completing the deal by January 2005.