Gov. Haley Barbour (R-Miss.) on Sunday defended Gov. Bob McDonnell's (R-Va.) decision to declare "Confederate History Month" without acknowledging the role of slavery.

McDonnell's declaration upset many who considered it inappropriate to honor the confederacy without condemning slavery.

But Barbour, chairman of the Republican Governors Association (RGA), said Virginians know slavery is immoral without being reminded.

"I don't really see what to say about slavery, but anybody that thinks you have to explain to people that slavery is a bad thing--I think that goes without saying," he said on CNN's "State of the Union."

"It's trying to make a big deal out of something that doesn't amount to diddly," Barbour said on the controversy.

Barbour said his legislature, controlled by Democrats, has honored Confederate veterans in a similar manner to what McDonnell had proposed.

"Maybe they should talk to my Democratic leiglsature, which has done the same thing ," Barbour said.

President Barack ObamaBarack Hussein ObamaOvernight Energy: Dems ask Pruitt to justify first-class travel | Obama EPA chief says reg rollback won't stand | Ex-adviser expects Trump to eventually rejoin Paris accord Overnight Regulation: Trump to take steps to ban bump stocks | Trump eases rules on insurance sold outside of ObamaCare | FCC to officially rescind net neutrality Thursday | Obama EPA chief: Reg rollback won't stand Ex-US ambassador: Mueller is the one who is tough on Russia MORE said Friday it was "unacceptable" to omit references to slavery in a Confederate History Month.

A few days after issuing the proclamation, McDonnell apologized for what he called a "major omission."

"The failure to include any reference to slavery was a mistake, and for that I apologize to any fellow Virginian who has been offended or disappointed," McDonnell said.

The Virginia Republican said he would add language to the proclamation describing slavery as an "evil and inhumane practice" that "led to this war."