Mexico has condemned a migration bill being debated by the US Congress, saying it is too focused on securing its 3,220-km (2,000-mile) border.
Many Mexicans try to cross the border with the US in search of a job
The House of Representatives backed the building of a border fence, the use of troops and police to halt migrants, and tighter employment controls.
The US Senate is due to debate the bill in turn in February.
A spokesman for Mexican President Vicente Fox said security alone could not solve immigration problems.
Ruben Aguilar added that his compatriots in the US made "an enormous contribution to the US economy".
The House voted 239-182 for legislation which:
The Bush administration is broadly backing the bill
- forces employers to verify the status of workers and raises fines against those who knowingly hire illegal aliens
- orders the construction of a hi-tech fence along parts of the US border with Mexico and asks for a study on using barriers along the Canadian border
- makes it a felony to live in the US illegally instead of a civil offence and toughens penalties for document fraud
- enlists military and local law enforcement to help stop illegal entrants.
A controversial call to deny babies born to illegal residents US citizenship was not allowed into the legislation.
Language expressing support for a guest worker programme proposed by President George W Bush was also left out of the bill on the grounds that it constituted an amnesty.
'Home by the millions'
Rep Thomas Tancredo, a Republican, said the House bill would discourage illegal immigrants by clamping down on lure of work.
"You will find people will go home and they will go home by the millions," he said.
"Those who don't go home, you deport."
Cross-party opponents in the US say the measures will be ineffective.
On Wednesday, Mexican President Vicente Fox described current US immigration policy as shameful and ignominious.
Critics of the bill say some of the measures would be impossible to enforce and would push illegal immigrants further underground.
They say the proposed reforms fail to tackle employers who use illegal immigrants or deal with the impoverished regions they come from.