Mexico raised the stakes in the battle against the bill, approved by the House of Representatives last week, by hiring a U.S. public relations firm and organizing a separate U.S. lobbying campaign against it.

"Mexico is not going to bear, it is not going to permit and it will not allow a stupid thing like this wall," Foreign Relations Secretary Luis Ernesto Derbez said, adding the government will do "whatever is needed" to oppose the measure.

"What has to be done is to raise a storm of criticism, as is already happening, against this," he said.

Derbez said he would take the issue to the international community, in an effort to build opposition to the measures.

Mexico is organizing U.S. church, community and business groups to oppose the proposal, and it has hired Allyn & Company, a Dallas-based public relations company, to help improve the country´s image and stem the immigration backlash.

"If people in the U.S. and Canada had an accurate view of the success of democracy, political stability and economic prosperity in Mexico, it would improve their views on specific bilateral issues like immigration and border security," Rob Allyn, president of the PR firm, told The Associated Press on Tuesday.

The government has countered by pledging to fight abuse of migrants living in the United States, airing a series of radio spots here aimed at Mexicans returning home for the holidays.

"Had a labor accident in the United States? You have rights ... call," states the ad, which is sponsored by Mexico´s Foreign Relations Secretariat. The department has helped migrants bring compensation suits in the United States.

Countries like Guatemala - whose own immigrants would be affected - blasted the measures.

President Oscar Berger described the bill as "absurd and offensive." It would also enlist military and local law enforcement to help stop illegal entrants.

It´s hard to underestimate the ill-feeling the proposals, which include building 1,100 kilometers (700 miles) of border walls, have generated in Mexico. Editorial pages are dominated by cartoons of Uncle Sam putting up walls that are often depicted as bearing anti-Mexican messages.

Fernando Robledo, 42, a former migrant worker from the western state of Zacatecas, says the proposals could disrupt families by making immigration harder.

"When people heard this, it worried everybody, because this will affect everybody in some way, and their families," Robledo said. "They were incredulous. How could they do this, propose something like this?"

Like many Mexicans, he expressed a sense of betrayal and rejection.

"We learned to believe in the United States. We have a binational life," he said of Zacatecas, a state that has been sending migrants north for more than a century. "It isn´t just a feeling of rejection. It´s against what we see as part of our life, our culture, our territory."

The feeling of dread is not restricted to Mexico.

U.S. immigrant rights groups are worried that anyone who aids or befriends immigrants could be subject to prosecution under provisions of the House bill, which would upgrade unlawful presence in the United States from a civil offense to a felony.

"It would have a horrific impact on immigrants right organizing and immigrant communities" in the United States, said Jennifer Allen of the Tucson, Arizona-based Red de Accion Fronteriza.

Mexico argues existing barriers have only pushed migrants to more desolate, dangerous areas. At least 415 people, a record, died crossing the border illegally in the latest full year, according to U.S. Border Patrol for the fiscal year ending Sept. 30.

The mistaken belief that the proposals are a done deal - they must still be submitted to the Senate - have caused "complete fear and shock" among some activists and immigrants, Allen said.

Christian Ramirez of the American Friends Service Committee in San Diego said the bill could "push underground the work of civil rights organizations" in the United States.