"We're going to get control of our borders and make this country safer for all our citizens," said Bush. He commented as he signed into law a $32 billion homeland security bill that has large increases for patrolling borders but fewer grants for local first responders and a freeze in transit security funding.
Hours earlier, administration officials appeared on Capitol Hill to promote the guest worker plan, saying action is needed beyond improving border patrols to stem the flow of illegal immigrants.
"We're going to need more than just brute enforcement," Homeland Security Secretary Michael Chertoff told the Senate Judiciary Committee. "We're going to need a temporary worker program as well."
Bush last year introduced a plan that would allow undocumented workers to get three-year work visas. They could extend that for another three years, but would then have to return to their home countries for a year to apply for a new work permit.
The president called his proposal a necessity for an economy that needs employees for jobs many Americans don't want.
"I'm going to work with members of Congress to create a program that can provide for our economy's labor needs without harming American workers, without providing amnesty and that will improve our ability to control our borders," Bush said.
Seeking to mollify balky Republicans, Bush emphasized border-control measures. He said the bill he signed would help in deporting illegal immigrants and would provide more border patrol agents, new immigration-fighting technologies and expanded detention centers.
GOP leaders in both the House and Senate have suggested that Congress should first take up the enforcement issue, putting off debate on the more complex issues of undocumented workers and the demand for low-skilled labor in this country.
But Judiciary Committee Chairman Arlen Specter, R-Pa., said that with reports of larger numbers of illegal immigrants - often estimated around 11 million - than legal immigrants, his panel would address comprehensive change. "It is a matter of very, very substantial urgency," he said.
Mexico said Tuesday that any U.S. immigration reform plan would have to "recognize the contributions of migrants" and take into consideration those already living north of the border, but appeared to cautiously praise the position laid out by the Bush administration.
"The Mexican government considers it significant that the administration ... has a solid and unified position on immigration reform that allows safe, legal and orderly migration, and takes into account those migrants who are already residing in the United States," the Foreign Relations Department said in a press statement
Labor Secretary Elaine Chao said workers accepted into the program would be issued biometric, tamper-resistant cards that would allow them to cross U.S. borders during their stay.
"Those who come forward will not be offered an automatic pass to citizenship and should be expected to pay a substantial fine or penalty to participate in the temporary program," she said.
Several members of the committee are sponsoring legislation that, in addition to strengthening border security and workplace enforcement, would set up guest worker programs.
Sen. Edward Kennedy, D-Mass., with Sen. John McCain, R-Ariz., has a bill that would provide visas for up to six years, after which the worker must either leave the country or be in the pipeline for a green card.
Sens. John Cornyn, R-Texas, and Jon Kyl, R-Ariz., have a rival bill that would require illegal aliens to return to their home country to apply for the temporary worker program.
Speaking at a Chamber of Commerce forum on illegal immigration Tuesday, McCain said any plan centered on sending illegal immigrants home ignores that businesses rely on immigrant labor and that many immigrants have children born in the United States, who are citizens.
Chertoff also pledged to end the "catch and release" policy that has allowed tens of thousands of non-Mexican illegal aliens to disappear within the United States.
"Return every single illegal entrant - no exceptions," Chertoff said in prepared testimony to the committee.
Chertoff said that the nearly 900,000 Mexicans who are caught entering United States every year are returned immediately to Mexico, "but other parts of the system have nearly collapsed under the weight of numbers."
Chertoff said that in the just-concluded budget year 120,000 of the 160,000 non-Mexican nationals apprehended by the Border Patrol were released, often on their own recognizance, because there is no place to hold them. "That is unacceptable and we are going to change that immediately."
He agreed with Kennedy that trying to deport all illegal immigrants would not be possible.