Michael Bonfigli / Michael Bonfigli AFL-CIO President Richard Trumka speaks at the St. Regis Hotel on August 29, 2013 in Washington, DC.

The head of the nation’s largest federation of unions admitted “we made some mistakes” in writing ObamaCare Thursday at a Christian Science Monitor breakfast in downtown DC. The head of the AFL-CIO, Richard Trumka, said he was surprised that employers have reduced workers’ hours below 30-a-week to avoid an employer penalty scheduled to go into effect in 2015.

“That is obviously something that no one intended. No one intended the act to result in people working fewer hours just so they [employers] don’t have to pay for healthcare,” said Trumka. “So that’s something that needs to be addressed. Is that an issue? Yeah that’s an issue.”

Local governments, movie theater chains, and fast-food restaurants have announced cut backs in hours due to ObamaCare. Last week, Reuters reported that an effort to reduce hours “might have helped push the average work week down to a six-month low in July.” Yet some, like the Washington Post‘s Sarah Kliff, have noted that the vast majority of large employers haven’t dodged the requirement.

When asked if he would accept a change in ObamaCare’s definition of full-time work, as some legislators have suggested, Trumka responded, “Of course we would,” but didn’t elaborate on what the change would be.

The selling of ObamaCare to the American public has become an obsession in the White House. Yet the implementation has had its share of bumps, including the announcement in July that the employer mandate requirement would be delayed until 2015. Trumka at the time called the move “troubling.” Another “mistake” was dropping the public option, Trumka said at the breakfast.

But overall Trumka is pleased with the health care law, calling it a “major step in the right direction” that “still needs to be tweaked.”