"There are initiatives in (the U.S.) Congress that provide solutions to the problem of migration, so we'll keep on having an optimistic, positive ... attitude," said Fox, who met with foreign correspondents in Mexico City.

The comments came despite a tough speech by U.S. President George W. Bush on Monday in which he promised more border enforcement and no amnesty for undocumented migrants.

Bush has stressed his support for a temporary guest worker program, but that plan envisions having most workers return home after up to six years working in the United States. Mexico is pushing for more permanent, legal residential status.

Fox said the two nations need to work out details of how many Mexicans would be allowed to work legally in the United States and in what sectors of the economy.

‘ORDERLY FLOW’

"The best thing that can happen to both our countries is to have an orderly flow, a controlled flow, of migration to the United States," Fox said, adding that Mexicans "contribute enormously to the U.S. economy, to U.S. competitiveness."

Fox said his government will continue to insist on the protection of the rights of Mexicans working abroad, but he backed off Mexico's traditional opposition to U.S. plans to build a wall along the entire border.

"It's their territory," he said. "They can do whatever they want in their territory."