Bush has spoken approvingly of Brazil's ethanol programme, which powers eight out of every 10 new Brazilian cars.
Discussions between the two countries will aim to build a programme that will turn ethanol into an internationally traded commodity and to promote sugarcane-based ethanol production in Central America and the Caribbean.
Brazil is the world's biggest exporter and consumer of ethanol as an alternative fuel.
It has been enthusiastic about proposals to join forces with the US and create a world wide market for ethanol.
But not everyone is optimistic.
Mariana Schwarz, a 25-year-old publicist said: "We know that Bush and the United States are known for exploiting weaker countries into deals that will only benefit themselves without worrying about the environment."
Suzanne Pereira dos Santos, an activist with Brazil's Landless Workers Movement said: "Bush and the United States go to war to control oil reserves, and now Bush and his pals are trying to control the production of ethanol in Brazil. And that has to be stopped,"
|Bush's visit will take in Brazil, Uruguay,|
Colombia, Guatemala and Mexico [AFP]
Graffiti reading "Get Out, Bush! Assassin!" appeared on walls near the locations that Bush will drive past as he begins a Latin American tour that also includes stops in Uruguay, Colombia, Guatemala and Mexico.
Over the last six years, while some argue that Bush has ignored Latin America, many of the nations in the region turned to Hugo Chavez, Venezuela's president, for both leadership and money.
Romeo Perez Anton, a political analyst in Uruguay, told Al Jazeera: "The rhetoric, the proposals of Chavez, have finally opened the eyes of the United States, and I think this is the explanation for this diplomatic offensive."
Thomas Shannon, a US assistant secretary of state, said: "The president's trip to the region gives us a great opportunity to say yet again how we are engaged in the region, to underscore our commitment to the region."
'Worst US leader'
Washington has lost its once undisputed economic and political influence in the region and the trip is intended to dispel feelings that the US has been neglecting its regional neighbours.
Bush has been rated the worst US leader in recent memory in Latin America.
|The graffiti reads: "Bush fascist go to hell" [AFP]|
After talks with Luiz Inacio Luiz da Silva, the Brazilian president, Bush will head on Friday to Uruguay, where he will meet his counterpart Tabare Vazquez.
Chavez will travel to Buenos Aires to lead protests against Bush on Friday. Bush will not visit Argentina.
In Mexico City, which Bush is scheduled to visit on Tuesday, about two dozen demonstrators gathered in front of the US embassy chanting slogans against the US project to construct border fences and Bush's visit.
Roman Diaz Vazquez, a lawyer and protest leader, said: "Why is he coming here? It makes no sense, it's unreasonable, after all he's done."
Jose Mujica, Uruguay's minister of agriculture and once a Tupamaro guerrilla fighter, told Al Jazeera he hoped Bush's overtures towards Uruguay would give the tiny and often ignored country more clout with its neighbours.
"We depend ferociously on Brazil and Argentina but they don't depend on us. Sometimes they need to be reminded that we exist," he said.
Mujica hopes US overtures towards Uruguay will
give the country more clout with its neighbours
Despite concerns over unity in Latin America, if Bush's plan is to counter the Chavez charm offensive in the region, Washington may have its work cut out.
Lula Da Silva, Brazil's president, has made it clear that his priority is unity between Latin American states, which includes, rather than isolates, Venezuela.