WASHINGTON - The House moved to deny driver's licenses to illegal immigrants and to tighten asylum laws - offering the first salvo in what is sure to be a contentious debate over immigration on Capitol Hill this year.

On a 261-161 vote, the House approved legislation Thursday that backers say would improve border security and hamper terrorists' ability to travel inside the country.

"The goal of the Real ID Act is straightforward. It seeks to prevent another 9/11-type terrorist attack by disrupting terrorist travel," said the bill's author, Rep. James Sensenbrenner, R-Wis. Not so, said a broad swath of critics, who charged that the measure's champions used the threat of terrorism to crack down on immigrants and asylum seekers while placing the financial burden on the states. The bill was opposed by immigrant and refugee advocates, state motor-vehicle administrators, the National Governors Association, religious groups and civil libertarians. "It will make it harder for those fleeing religious and political persecution to access freedom; prevent legal immigrants from becoming citizens; put more unlicensed and uninsured drivers on our roads; and make the government exempt from labor, environmental, contract, immigration, health, safety and other laws when constructing border barriers," said Angela Kelley, deputy director of the National Immigration Forum. Though the legislation gained a boost this week with a White House endorsement, its prospects in the Senate are unclear. Several key Senate Republicans have said the bill should be considered as part of a broader immigration debate, including President Bush's proposal to grant guest-worker status to many of those living illegally in the United States. In hopes of forcing the Senate to act on the bill, House Republican leaders intend to roll it into the first must-pass legislation of the year, likely to be the supplemental funding for the war in Iraq. That move could set up a confrontation with Senate GOP leaders, who have said they don't want to load the Iraq bill with extra measures. The legislation also mandates completion of a border fence near San Diego that has been held up amid environmental concerns. House Democrats complained that the bill is so broadly written that it permits the homeland-security secretary to sidestep all judicial scrutiny and waive all federal laws along the border - not just for completion of the fence. "No person in our country should be given unfettered authority and unfettered discretion to waive any and all laws, whatever the purpose," said Rep. James Oberstar, D-Minn.