Republican presidential candidate Nikki Haley responded to "sexist" claims made by CNN host Don Lemon, who claimed the former United Nations ambassador is past her prime at age 51. 

Haley joined "America's Newsroom" Friday to discuss how the left-wing media has responded to her announcement to challenge former President Trump and others for the GOP nomination. 

Lemon, who commented on Haley's age Thursday on "CNN This Morning," quickly faced criticism for his comments, even from his co-hosts.

"This whole talk about age makes me uncomfortable. I think it’s the wrong road to go down. She says people, you know, politicians are something if not in their prime. Nikki Haley isn't in her prime, sorry. A woman is considered to be in their prime in 20s and 30s and maybe 40s," said Lemon, who is 56.

TRUMP'S IN - SO IS HALEY - HOW LARGE WILL THE GOP 2024 FIELD GROW?

Co-host Poppy Harlow questioned what he meant by "prime" and Lemon said that it wasn't according to him.

"I’m just saying what the facts are. Google it. Everybody at home, when is woman in her prime, it says 20s, 30s and 40s. And I’m just saying should be careful about saying that politicians are not in their prime and they need to be in prime when they serve. Because she wouldn't be in her prime…," Lemon said.

Lemon later expressed "regret" for his comments on Twitter and further apologized to his CNN colleagues on a Friday call. 

"It was Don Lemon yesterday, it was Whoopi Goldberg the day before. There will be somebody else tomorrow. I have always made the liberals' heads explode." Haley told Sandra Smith and Bill Hemmer.

"They can't stand the fact that a minority conservative female would not be on the Democratic side because they know I pull independents. They know I pull suburban women. They know I pull minorities over to what we are trying to do." 

Haley continued to emphasize her point that politicians need to be competent in order to lead.

"I wasn't sitting there saying sexist, middle-aged CNN anchors need to have mental competency tests, although [Lemon] may have just proven that point. What I was saying is we need to be transparent. Those elected officials that are making key decisions for Americans on national security and keeping our kids safe and the debt. Yes, we need to know exactly that." 

Haley said liberals like Lemon will continue to "show themselves" because they "can't stand" women who are on the conservative side.

"In the America I see, the permanent politician will finally retire," Haley said as she formally announced her run for president from Charleston, South Carolina. "We’ll have term limits for Congress and mandatory mental competency tests for politicians over 75 years old."

Haley's proposed rule would impact former President Donald Trump, 76, who has declared his candidacy for president in 2024, and President Biden, 80, who has not yet made his plans official.

Fox News' Paul Steinhauser and Thomas Phippen contributed to this report.