The United States and Brazil have entered a new partnership to promote the production of ethanol around the world.
The presidents of the United States and Brazil say they have a vision -- a vision of a world where the production and consumption of biofuels is commonplace.
President Bush says it is a goal worth meeting.
"I hope the people of the United States and the people of Brazil are as optimistic about the future as these two presidents are. And one reason we are optimistic is because we see the bright and real potential for our citizens to be able to use alternative sources of energy that will promote the common good."
Mr. Bush spoke after touring an ethanol distribution facility in Sao Paulo with the president of Brazil, Luis Inacio Lula da Silva. Earlier, foreign ministers from the two countries signed an agreement designed to promote research and development of biofuels and to set the standards for ethanol to become a recognized commodity on world markets.
Together, the United States and Brazil produce about 75 percent of the world's ethanol. But Brazil is the largest exporter, and the undisputed leader in biofuel technology.
President Bush said he wants to work with the Brazilians to expand production and make ethanol more affordable. He said in time, other developing countries will be able to join in and use raw agricultural materials -- such as sugar cane and grasses -- to develop their own fuels.
"I appreciate so very much the idea of Brazil and America sharing research and development opportunities. You have got great scientists. We have got great scientists. It makes sense for us to collaborate for the good of mankind."
The development of alternative fuels has become a key element of the Bush administration's energy policy. And President da Silva, speaking through a translator, said he deserves some of the credit, noting he brought up the subject during their last meeting in Brazil about a year and a half ago.
"I was truly obsessed with biofuel. And he almost couldn't have lunch because I wouldn't stop talking about biofuel. But I think that was important because the world is not always ready and prepared for major changes."
Both men talked about the ability of biofuel production to create jobs in the developing world, and cut dependence on oil imports. Among the countries which could lose out in the future if biofuels catch on is Venezuela, one of the world's largest oil exporters.
Venezuelan leader Hugo Chavez has been using oil revenues in an effort to build a following throughout the hemisphere. He is taking part in an anti-American rally later Friday in Argentina.
Anti-Bush protests have taken place here in Sao Paulo, where discontent with the Iraq war has made the U.S. president highly unpopular. There was some violence Thursday, but most demonstrators have been peaceful. They include farmers worried that they might be exploited by companies eager to expand ethanol production, and environmentalists concerned that the Amazon jungle might be destroyed in the rush to plant sugar cane.
But the biggest security concerns for the traveling White House may be in Bogota, Colombia, which Mr. Bush will visit on Sunday. Police officials there say there are signs Colombian rebels are planning attacks, but add security precautions are already in place.
In addition to Brazil and Colombia, President Bush will also travel to Uruguay, Guatemala and Mexico before returning home next Wednesday.