President Barack Obama speaks about the Affordable Care Act on Thursday at Prince George's Community College in Largo, Md. (Pablo Martinez Monsivais/AP)

The Obama administration has delayed yet another piece of the health care overhaul, pushing back online enrollment for small business owners on the new federal health insurance exchange, a Department of Health and Human Services source tells The Washington Post.

On the federal exchange, which is scheduled to launch on Tuesday, small business owners will not be able to purchase coverage online until Nov. 1. Instead, for the first month, they will have to mail or fax their information to government officials to enroll on the federal exchange, which will serve individuals and business owners in the 34 states that elected not to set up their own exchanges.

Plans purchased through the small-business exchange will still take effect Jan. 1, as planned, HHS spokeswoman Joanne Peters told The Washington Post.

White House Press Secretary Jay Carney downplayed the delay during a press conference on Thursday, noting that employers can enroll in coverage at any point during the year, whereas individuals have a limited window of time in which to enroll.

“Again, everything comes online on October 1,” Carney said.

This is the latest in a string of delays for the sweeping health care overhaul and is already providing Republicans with additional ammunition as they push to defund Obamacare.

“I’ve never seen a law implemented with so many delays, mistakes and problems,” House Small Business Committee Chairman Sam Graves (R-Mo.), said in an e-mail, adding that “its’ delays, false-starts and misinformation are leading to even more confusion and uncertainty for small businesses.”

White House officials in April announced they would delay for one year a key cost-cutting feature in the small-business exchanges. Originally, the marketplaces were supposed to allow business owners to offer various plans for different workers, but instead, for the first year, employers must choose one plan to cover their entire company.

Then in July, the administration announced that, for the first year, it would not enforce what is known as the “employer mandate” provision in the law, which would require firms with more than 50 employees to provide a minimum level coverage to their workers or pay a steep fine to the federal government.

More recently, some states — including Maryland and Washington — have announced that their small business owners will not have access to exchanges as planned on Oct. 1.

“With this latest glitch in the small-business exchanges, the case for a delay of the individual mandate alongside the employer mandate only grows stronger,” National Federation of Independent Business Manager of Legislative Affairs Kevin Kuhlman said in a statement. “Small-business owners should not be forced to comply with a law that is clearly not ready for prime-time.”

On Thursday, meanwhile, President Obama again pushed back against those aiming to dismantle the legislation, calling Republicans in Congress “irresponsible” for threatening the shut down the government if Democrats failed to drain the legislation of necessary funding.

“That’s not going to happen as long as I am president,” he said during a speech at “The Affordable Care Act is here to stay.”

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