Citing unnamed government sources, Reuters today reports what it says will be President Barack Obama’s main policy announcement during his upcoming visit to Brazil. The United States will offer hundreds of millions of dollars in loans for joint infrastructure ventures between American and Brazilian companies. The loans, which would be handled by the Export-Import Bank of the United States, would help US companies take a bigger bite of the building boom that’s set to occur here in the run-up to the World Cup in 2014 and Olympics in 2016.