Transportation Secretary Ray LaHood warned Sunday that if lawmakers don't avert across-the-board federal spending cuts set to begin Friday, the nation's air traffic controllers could face the prospect of being furloughed, reiterating comments he made last week that the cuts could have a substantial impact on air travelers.

"We're going to try to cut as much as we possibly can out of contracts and other things that we do, but in the end there has to be some kind of furlough of air traffic controllers," LaHood said on CNN's "State of the Union." "And that then will also begin to curtail or eliminate the opportunity for them to guide planes in and out of airports."

LaHood's remarks echoed what he said at the White House on Friday, when he warned of layoffs and delays if the deep cuts split between defense and domestic spending known as the sequester kick in. Some $600 million in cuts are expected to hit the Federal Aviation Administration.

LaHood, who served as a Republican congressman from Illinois before joining the Obama administration, pressed GOP leaders on Capitol Hill to come forward with an acceptable plan for averting the cuts.

"I am a Republican. My audience is trying to persuade my former colleagues that they need to come to the table with a proposal, which frankly they haven't done. While the president has, the Republicans haven't," LaHood said.

On NBC News' "Meet The Press," LaHood stressed that safety would not be compromised as a result of the cuts, but they could slow the pace of travel.

"We will never take a back seat to safety. Safety will not be compromised," he said. "But we will have to work with the airlines in slowing planes down. But there'll be enough controllers to make sure planes are guided in and out of airports safely."