Secretary of State Colin Powell and Attorney General John Ashcroft were due to meet Thursday with Mexican Foreign Secretary Jorge Castaneda and Interior Secretary Santiago Creel.
State Department spokesman Richard Boucher said Wednesday the administration is ruling out an amnesty for the large numbers of U.S.-based Mexicans who lack proper documentation.
Instead, he said, the administration is open to discussions on allowing Mexicans to work legally on a temporary basis in the United States. Similar permission would be granted to some Mexicans already working illegally in the U.S.
The two sides hope to be able to make progress on these issues ahead of Mexican President Vicente Fox's official visit to Washington in early September.
Mr. Bush and Fox discussed the issue during Bush's February visit to Mexico.
Fox said in late July that all Mexicans working in the United States should be legalized in recognition of their contribution to the U.S. economy.
He urged Mr. Bush and the U.S. Congress to approve a plan that would grant guest-worker status and eventually legal residency to 3 million illegal Mexicans.
Sen. Joe Lieberman, D-Conn., said during a visit to Mexico City this week that many in Congress favor granting some form of legal status to millions of Mexican migrants.
But he said officials on both sides of the border have yet to work out how many Mexicans would benefit from any new concessions.
Congressional conservatives generally have opposed anything beyond allowing Mexicans to stay as temporary laborers. The consideration of even limited amnesty is a divisive political issue, particularly in border states and among Republicans in Congress. There also is stiff opposition from anti-immigrant groups.
Granting legal residency to all Mexican immigrants now living in the United States is "very bad policy," said Sen. Phil Gramm, a Republican from Bush's home state of Texas. "It rewards lawlessness."
But Fox disagrees. "It isn't fair to consider them illegal when they are employed, when they are working productively, when they are generating so much for the American economy," Fox said last month. "They shouldn't have to walk around like criminals or stay hidden."
The United States already runs a program for guest workers called H-2A, in which farmers apply for the right to employ foreigners after first getting certification that there are no Americans to fill the jobs.
The Congressional Research Service reports that 28,560 H-2A workers were admitted in 1999. There are 1.2 million farm workers nationwide.
Some opponents believe the H-2A program is a disservice to American farm workers. Others claim the program does not do enough to ensure that migrant workers are treated properly.
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