Villaraigosa, whose grandfather and parents emigrated from Mexico to the United States, went beyond the usual rhetoric of "friendship" used by most visiting U.S. politicians, painting instead a picture of two nations historically and inevitably linked.

"Our fates are intertwined and indivisible and we need to stand and to stay united," he told a gathering of the U.S.-Mexico Chamber of Commerce on the first day of a planned weeklong tour of several Mexican cities.

"Ours is a common destiny. Our fates are indivisible."

Migration in particular, he said, needs to be seen as a bilateral issue.

"In Los Angeles, we understand that immigration is a problem that must be soberly and seriously addressed on both sides of the border," he said.

Villaraigosa said U.S. leaders need to provide a permanent pathway to citizenship for the nearly 12 million immigrants living there, and to reform the migration laws in a way that acknowledges that it´s that country´s own labor demands that has been fueling the flow of undocumented immigrants.

Mexican leaders, on the other hand, must address the needs of the desperately poor, enforce their own southern border, and accept that controlling its own borders is a legitimate U.S. concern, Villaraigosa said.

"Illegal immigration hurts us all," he said.

At a bilingual news conference after the business luncheon, the mayor had especially harsh words for some immigration reform proposals promising to dominate the 2008 election campaigns, which have already begun.

"It´s illogical to say you´re in favor of immigration reform and then speak of walls," he said. "Or to say you´re going to deport 12 million people."

The U.S. Congress has voted preliminary approval for a US$50 billion wall along much of the border with Mexico, while many Republicans and some Democrats oppose making undocumented immigrants eligible for U.S. citizenship, calling it "amnesty."

Villaraigosa was peppered Thursday with questions about the televised beating by police officers of a number of demonstrators and at least one news cameraman at a May 1 pro-immigrant march in downtown Los Angeles.

The victims were mostly Mexican or of Mexican descent, and the events have drawn wide- spread news coverage in this country.

The mayor, who was in El Salvador at the time, said he has ordered a full investigation. It was reported Thursday that the chief of police has asked the Federal Bureau of Investigation (FBI) to join the investigation, and Villaraigosa said he would support that action.

"I was disturbed by the television images," said the mayor, who began his political career as an immigrants´ rights activist in the 1970s. "I didn´t like what I saw."

Villaraigosa is fluent in Spanish with some stumbles, but prefers to give formal speeches in his first language, English. He spoke mostly in English to the U.S.-Mexico Chamber and mostly in Spanish to the media afterward.

Villaraigosa has spent considerable time in Mexico during the previous three presidential administrations, but this is his first visit since being sworn in as mayor on July 1, 2005.

Los Angeles, the United States´ second-largest and most multi-ethnic city, is home to more Mexicans than any city outside of Mexico City.

The mayor dined privately with President Calderón Thursday evening, and will talk to federal legislators and his Mexico City counterpart, Marcelo Ebrard, on Monday.

He will also visit the cities of Puebla, Guadalajara, León and Guanajuato, as well as former President Fox´s ranch in San Cristóbal, Guanajuato.