With open enrollment for Obamacare about to begin, small- and medium-sized businesses are not hiring because of uncertainty surrounding the implementation of the law, the CEO of nation's fifth-largest staffing company said on Monday.



"Companies are really not interested in hiring full-time people. That's really the issue with Obamacare," Express Employment Professionals boss Bob Funk told CNBC's "Squawk Box" on Monday.

Funk, a former chairman of the Kansas City Federal Reserve, admitted that this trend is a "boon" for his business, but "not healthy for the country as a whole."

(Read more: Most Americans against defunding Obamacare: Survey)

On October 1, consumers are scheduled to be able to buy health insurance from state exchanges for coverage effective Jan. 1, 2014. Most individuals are required to carry insurance under President Barack Obama's 2010 Affordable Care Act or face fines.

Back in early July, the White House and the Treasury Department announced a one-year delay in a major provision that would have required employers with at least 50 full-time workers to provide health insurance or pay a penalty. That'll now go into effect in 2015.

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Steven Rattner, Obama's former auto czar at Treasury, disputes Funk's assertions. "I don't think with the approach of Obamacare you see in the numbers people suddenly stopping hiring.

"Everybody has these anecdotal reports of this and that, and certainly the logical argument, they're going to go to part-time, but you just can't find it in the numbers," argued Rattner, current chairman of Willett Advisors.

Funk countered, "We're out there on Main Street and Obamacare is affecting the job hiring picture. Whether it's in the numbers or not, it is affecting small and medium-sized businesses. They're not going to hire until they know what their costs are going to be."

"We don't know what the rules are going to be," Funk added. "But they haven't written half of the rules … and it's affecting business, and permanent hiring out there. That's why our industry is growing quite rapidly."

Rattner conceded at least something of Funk's point.

"I don't doubt that Obamacare has created a temporary period of uncertainty," he said. "If you're going to tell me Obamacare is the cause of the tepid recovery for the last five years, I think that's a stretch."

—By CNBC's Matthew J. Belvedere. Follow him on Twitter @Matt_SquawkCNBC.

