Illegal immigrants in the United States gathered Monday for a day of nationwide rallies and demonstrations in another protest against proposed immigration reform.

Millions of immigrants were expected to stay away from work, school and stores as part of a mass boycott against the country's new immigration laws.

In one of the earliest demonstrations of the day, about 1,200 marched in the town of Homestead in rural Florida, home to a large Latino population.

Meanwhile, crowds gathered in Los Angeles, and New Orleans, but it was too early to gauge how many people would turn out.

The protest, called a 'Day Without Immigrants' ('Un Dia Sin Immigrantes'), is an attempt to prod President George Bush and a divided Congress to enact legislation to protect the estimated 12 million people living illegally in the United States.

The rallies also spread to Mexico and other Latin American countries, where people have been urged to boycott U.S. products for the day.

At least a half-dozen state governors in Mexico endorsed the boycott of McDonald's, Wal-Mart and hundreds of U.S. products Monday, while thousands of union members rallied to support Mexican migrants working in the United States.

"I hope it will be a wake up call to U.S. Congress, who passed a law in December 2005 to criminalize immigrants who have been here a long time," Felipe Aguirre, Vice-Mayor of Maywood, California told CTV's Canada AM Monday.

"This is something that has really captured the imagination of a lot of immigrants."

Immigrant amnesty

Organizers of the demonstration want to pressure Congress -- which has mid-term elections this fall -- into granting an amnesty and eventual citizenship for the undocumented immigrants, most of whom are from Mexico.

Political conservatives, however, want to classify illegal immigrants as felons. They also want to build a fence along the Mexican border.

Organizers say direct action is the only way to advance their cause, but critics of the boycott say it is essentially blackmail and will harden public opinion against illegals.

The organizers predict many of America's major cities will grind to a halt Monday as the immigrants walk off their jobs, skip school and attend rallies.

The U.S.'s construction, agriculture and meat-packing are among those expected to be significantly affected.

In California, which has more undocumented workers than any other state, the State Senate has endorsed the planned day of action. 

Lawmakers approved what they called "the great American boycott of 2006", describing it as an attempt to educate Americans about "the tremendous contribution immigrants make on a daily basis to U.S. society and the economy.

At least 500,00 people are expected to take part in Los Angeles alone.

And in New York, organizers said a growing number of businesses had pledged to close and allow their workers to attend a rally in Manhattan's Union Square.

Teachers' unions in major cities have said children should not be punished for walking out of class.

However, not all supporters of the illegal immigrants are planning a full day of economic boycott.

Some plan to go to work but not buy anything, while others will protest during their lunch break.

The U.S. Conference of Catholic Bishops urged immigrants to attend mass instead of boycotting, and suggested that churches toll their bells in memory of immigrants who died trying to come to the U.S.