NASHVILLE, Tenn. – President Bush sharply challenged critics of his stalled immigration-overhaul efforts on Thursday, suggesting that failure to pass a guest-worker program could trigger a labor shortage in the United States.

At a town-hall style meeting, Bush also rebuffed a question about whether he would consider pardoning two Border Patrol agents in prison for the cover-up of the shooting of a drug trafficker in Texas.

“No, I won’t make you that promise,” Bush told a woman who asked about a possible pardon. Many Republicans in Congress have said the men should not have been convicted and have criticized the federal U.S. attorney for even prosecuting the agents.

“I know it’s an emotional issue but people need to look at the facts. These men were convicted by a jury of their peers after listening to the facts” as presented by U.S. Attorney Johnny Sutton, said Bush. Bush called Sutton a friend.

The president also toured a bun bakery here, and used the business to illustrate a warning to Congress that he’d veto any government spending bill that he thinks is excessive.

“You can’t keep making buns if the Democrats take all your dough,” Bush joked in a speech shortly after taking in the aroma of fresh bread at the bakery, which supplies fast-food restaurants.

Bush took questions for more than an hour. Most were friendly, but several on immigration policy were pointed.

The president said he was disappointed about his immigration bill’s demise in the Senate and reiterated his support for a guest worker program and a path toward citizenship for many of the 12 million illegal immigrants now in the United States.

Without such a program, and with stricter enforcement of the border, said Bush, “I can make you a prediction … that pretty shortly people are going to be knocking on people’s doors saying `Man we’re running out of workers.”‘

The president defended his embattled Iraq policy and sought yet again to link the current Islamic militants in Iraq with those who planned the Sept. 11, 2001, terror attacks, even though such links are tenuous.

When Bush was asked about whether he would consider pardoning the two border patrol agents, he seemed briefly taken aback.

“I’m not going to make that kind of promise in a forum like this, obviously,” he said. “I’m interested in facts. I know the prosecutor very well, Johnny Sutton. He’s a dear friend of mine from Texas. He’s a fair guy. He is an evenhanded guy and I can’t imagine, well, you know. …”

To the woman, Bush said, “You’ve got a nice smile but you can’t entice me (into) making a public statement” on the controversy.

The issue of presidential pardons has been front and center since Bush last month commuted the 30-month jail sentence of I. Lewis “Scooter” Libby, the former chief of staff to Vice President Dick Cheney. Bush had called the sentence “excessive.”

The border patrol case has figured in the debate over overhauling immigration law. And calls for executive clemency have come from many Republican lawmakers. Former agents Ignacio Ramos and Alonso Compean are serving 11- and 12-year federal prison sentences, respectively, for the 2005 shooting.

The woman who asked the question of Bush told him that the Tennessee General Assembly has passed a resolution asking for such a pardon.

Bush’s visit was designed to focus on the economy.

He said the Democratic-led Congress should pass appropriations bills and make sure they keep spending in check, a key concern of his conservative base.

“I’ve got the right to accept whether or not the amount of money they spend is the right amount,” Bush said during the speech about his federal budget priorities at the Gaylord Opryland Resort Hotel and Convention Center.

“If they overspend or if they try to raise your taxes, I’m going to veto their bills,” he said.

Seven of the 12 annual spending bills have passed the House but none have passed the Senate, and it’s clear that the Oct. 1 deadline to enact the bills will go unmet.

Sen. Kent Conrad, D-N.D., chairman for the Senate Budget Committee, responded even before Bush left Nashville.

“How ironic that the White House would use a bakery as a backdrop, because when it comes to spending the people’s dough _ taxpayer money _ this president baked this cake,” Conrad said. He argued that since Bush took office, government spending has increased nearly 50 percent.

In his brief tour of the Nashville Bun Co., the president took in the smell of warm bread that filled the humid air. He hugged workers and posed for photos with them and watched small lumps of dough roll by on a conveyer belt.

The company supplies its top customer, McDonald’s Corp., with enough hamburger buns to feed most of the Southeast and the Caribbean.

When the president stepped off Air Force One, he was greeted by Army National Guard Sgt. James Kevin Downs, 21, of Kingston Springs, Tenn., a double-amputee and burn victim who sat in a wheelchair on the tarmac. He was injured in Iraq by an improvised explosive device and rocket-propelled grenade. “He’s a good man,” Bush said later during his speech.

Associated Press Writer Will York in Nashville contributed to this report.

A service of the Associated Press(AP)