"The treasury needs to reduce its dependence on petroleum," [Agustin Carstens] said. "The difficult challenge is to expand the tax base."

"We have a system that allows tax evasion in most cases if you have good accountants or good lawyers," said Mexican President Felipe Calderon, speaking at an event in the state of Tlaxcala. "In the fiscal system that we're proposing, and that the country needs, there must not be any privileges."

"This could double or triple the effective tax rate of small businesses," he said. "They are the ones providing most of the jobs."