President Bush pushed for improved border security and called on Congress to pass a comprehensive immigration bill during a trip to the U.S.-Mexico border on Monday.

"It's important that we get a bill done. We deserve a system that secures our borders and honors our proud history as a nation of immigrants," Bush told a group of border agents.

Bush made his second trip in less than a year to Yuma, Ariz., a 125-mile stretch overlapping Arizona and California.

The president pushed for improved border security, a temporary guest worker program and holding employers accountable for workers they hire.

“You cannot fully secure the border until we take pressure off the border. And that requires a temporary worker program. It seems to make sense to me that if you’ve got people coming in here to do jobs that Americans aren’t doing, we need to figure out a way that they can do so on a legal basis for a temporary period of time," Bush said.

Lawmakers have yet to agree how to address the issue of about 12 million illegal immigrants in the United States. Bush is hoping they reach a compromise by August.

Bush toured the “Predator,” an unmanned drone that border officials use to monitor the region, with Chertoff.

Border officials report that the number of arrests are down, which shows progress with fewer people attempting to illegally cross the border, Bush said.

"It's amazing progress that's been made. We have come back to this spot because it's where I was the last time. And I was most impressed by your strategy, even more impressed by the fact that it's now being implemented," Bush said.

Senate Majority Leader Harry Reid has set aside time in May for immigration debate.

White House spokesman Gordon Johndroe said although war in Iraq dominates the headlines, "there's a lot of quiet work that goes on underneath the surface, so that we can get some legislation done on issues like immigration.:

The White House will work with members from both political parties to get a comprehensive bill through Congress this year, Bush said.

Administration officials led by Homeland Security Secretary Michael Chertoff and Commerce Secretary Carlos Gutierrez have been meeting privately for weeks with Republican senators. That expanded to a meeting in late March with key senators from both parties.

Out of that session, a work-in-progress plan emerged — one described as a draft White House plan by officials in both parties and advocacy groups who got copies of the detailed blueprint.

The White House disputes that characterization. Spokesman Scott Stanzel said it was only a starting point, an emerging consensus of Republican senators and the White House.

The number of border crossers in the Yuma Sector is down 68 percent this year, according to the White House.

The Bush plan would grant work visas to undocumented immigrants but require them to return home and pay hefty fines to become legal U.S. residents. They could apply for three-year work visas, dubbed "Z" visas, which would be renewable indefinitely but cost $3,500 each time.

"There are a lot of proposals floating around out there," Johndroe said. "I don't want to negotiate from here. I'm going to let secretaries Chertoff and Gutierrez do that with members."

The undocumented workers would have legal status with the visas, but to become legal permanent residents with a green card, they'd have to return to their home country, apply at a U.S. embassy or consulate to re-enter legally and pay a $10,000 fine.

That's far more restrictive than the bipartisan bill the Senate approved last year.

So far, Bush has only gotten part of what he wants — border legislation. He signed a bill last October authorizing 700 additional miles of fencing along the U.S.-Mexico border.

The president has spent much of the last four days on vacation at his Texas ranch. He returns to Washington Monday after the Arizona visit.

FOX News' Mike Emanuel and The Associated Press contributed to this report.