BOISE - Lawmakers are returning to the nation's capital after a five-week break and have unfinished business on immigration.

But Idaho Republican Rep. Raul Labrador has expressed an increasing skepticism that any changes will pass this year, saying wide political differences and more pressing issues, such as Syria and the national debt, will prevent progress.

"I don't think there's going to be sufficient time for us to discuss immigration," Labrador said in a recent interview with The Associated Press.

Immigration has had a prominent place this year in the national conversation as Congress, prompted by President Barack Obama, has debated making changes to the nation's laws. The topic was expected to come up again at some point after lawmakers reconvene today in Washington, D.C.

Labrador said he and other members of Congress "were all hoping we would have a debate in October, now it looks like September and October are going to be pretty full with other issues."

On immigration, one of the president's priorities for his second term, the Democratic-led Senate advanced a sweeping immigration proposal in June that included a pathway to citizenship. House Republicans rejected that plan early last month with the promise to pass something more narrowly focused on border security.

With the talks trudging along, the acting director of U.S. Immigration and Customs Enforcement on Aug. 23 issued new instructions, telling authorities that before deciding to jail a person living in the country illegally they should consider whether that person has young children.

For his part, Labrador said these sorts of orders reflect the Obama administration's desire to advance its own immigration agenda without input from Congress.

"Obama is doing all these things unilaterally," Labrador said, adding such directives make it increasingly difficult to pass system-wide overhauls and undermine confidence.

"How can you force the administration to comply with new laws, when they're actually telling their enforcement agencies not to enforce the existing law?" Labrador asked.

"That's really the problem we have: A lack of trust in enforcement," he said.

Labrador, an immigration attorney who represents Idaho's 1st Congressional District spanning the state's west and north, has emerged as a leading voice on the issue, using his personal story and professional experience to advance his position. Labrador was born in the U.S. territory of Puerto Rico and moved to Nevada as a child with his mother. English is his second language, and he says he knows from experience the challenges of coming to a new land.

Until June, he was part of a bipartisan House committee, called the Gang of 8, seeking to craft an immigration bill. Labrador left the group in a dispute over health care. He has since emerged as a vocal critic of the Senate plan.

Among other things, Labrador wants better tracking of immigrants in the U.S., to make sure they leave when their visas expire. He also calls for giving local law enforcement more power to make immigration-related arrests.

"For me, I have drawn a red line on immigration," he said. "Will we have this debate 10 years from now? Are we actually fixing the problem, or are we just punting on the problem? The Senate bill just punts on the problem."

Immigrants' rights activists dispute Labrador's assertion that an overhaul is unlikely this year, saying faith-based organizations, agricultural associations and business all favor action this year.

"That pressure from all of these different sectors and industries is going to continue to push members of Congress to have a vote on immigration," said Laura Vazquez, National Council of La Raza's senior immigration legislative analyst in Washington, D.C.

Other observers say any action on the topic likely won't start until October since Congress has only nine legislative days in September.

Labrador, meanwhile, said other issues will push immigration to the back burner. In addition to discussions over whether to authorize the president's call for missile strikes in Syria in response to reports of use of chemical weapons against civilians, Labrador expects bitter debate over taming the nearly $17 billion U.S. debt.

Labrador welcomed House Speaker John Boehner's recent pledge, made in August during a Boise fundraiser for 2nd District Idaho GOP U.S. Rep. Mike Simpson, not to raise the debt ceiling beyond $16.7 trillion, absent cuts to programs such as Medicare, Medicaid and Social Security that exceed the debt-limit increase.

But Labrador, a critic of Boehner's moderate tendencies, also fears the Ohio Republican won't stick by this pledge as mid-October approaches. That's when U.S. Treasury Department officials predict the government won't be able to pay all its bills.

Democrats may call Boehner's bluff, he suggested. "I just hope he has the resolve to stick with it," Labrador said.