Donald Trump on Monday defended his running mate's claims that "childless cat ladies" had destroyed American values, but also said he believed adults without children were just as good as parents.

JD Vance's 2021 comment that Vice-President Kamala Harris and other Democrats were "a bunch of childless cat ladies miserable at their own lives" resurfaced after Trump selected the Ohio senator as the Republican vice-presidential candidate.

In a Fox News interview on Monday, Trump said that Mr Vance "likes families", but Trump also said he did not place a higher value on parenting.

"You know, you don't meet the right person, or you don't meet any person. But you're just as good, in many cases, a lot better than a person that's in a family situation," he said.

Ms Harris, the presumptive Democrat candidate, has two stepchildren with her husband, lawyer Doug Emhoff.

Mr Emhoff's ex-wife has called such attacks "baseless" and described Harris as a "loving, nurturing, fiercely protective" co-parent.

Trump said Mr Vance was simply trying to show how much he values family life.

"He grew up in a very interesting family situation, and he feels family is good. And I don't think there's anything wrong in saying that," Trump said.

"All he said is he does... like I mean, for him, he likes family."

Asked by Fox News television host Laura Ingraham on Monday whether he could vouch for Mr Vance as an "excellent pick" for the November election, Trump said: "He's got has tremendous support, and he really does among a certain group of people - people who like families."

"That does not mean that people who aren't members of a big family... he's not against anything. He loves family, it's very important to him."

Mr Vance defended his roundly criticised remarks, saying that it was "obviously... a sarcastic comment".

"People are focusing so much on the sarcasm and not on the substance of what I actually said," Mr Vance said during The Megyn Kelly Show on Friday.

"The substance of what I said, Megyn - I'm sorry, it's true," he added.

Mr Vance, who has three children, said he was not criticising people who do not have children.

"This is about criticising the Democratic Party for becoming anti-family and anti-children," he told .

"The simple point that I made is that having children, becoming a father, becoming a mother, I really do think it changes your perspective in a pretty profound way," he said.

"I'm making an argument that our entire society has become sceptical and even hateful towards the idea of having kids."

On Friday, Mr Vance said: "I wish her step-children and Kamala Harris and her whole family the very best. The point is not that she’s lesser. The point is that her party has pursued a set of policies that are profoundly anti-child."

In the original interview with Tucker Carlson, Mr Vance questioned why some leading politicians did not have children. He named Ms Harris as an example.

"The entire future of the Democrats is controlled by people without children," he said at the time. "How does it make any sense we've turned our country over to people who don’t really have a direct stake in it?"

The senator from Ohio said the country was being run "by a bunch of childless cat ladies who are miserable at their own lives and the choices that they've made and so they want to make the rest of the country miserable too".

Actress Jennifer Aniston, who has spoken publicly about her struggles to have children through in-vitro fertilisation (IVF), was among those who recently criticised his comments.

"I truly can’t believe that this is coming from a potential VP of the United States," she said on Thursday.

US Secretary of Transportation Pete Buttigieg, a Democrat, named by Mr Vance in the original interview, also addressed the comments earlier this week, speaking about adopting twins with his husband, Chasten.

"The really sad thing is he said that after Chasten and I had been through a fairly heartbreaking setback in our adoption journey," Mr Buttigieg told CNN’s The Source programme.

Speaking to Fox News, Trump co-campaign chairman Chris LaCivita rejected any suggestion that Trump might regret his choice of running mate.

"JD was the best pick," Mr LaCivita said. "The president loves him. We love him."