Republican leaders have warned party members against using overtly racist and sexist attacks against Vice President Kamala Harris as they and Donald Trump’s campaign scramble to adjust to a new Democratic presidential rival.

At a closed-door meeting of House Republicans on Tuesday, National Republican Congressional Committee (NRCC) chairman Richard Hudson urged members to stick to criticising Ms Harris for her role in policies.

“This election will be about policies and not personalities,” House Speaker Mike Johnson told reporters after the meeting.

“This is not personal with regard to Kamala Harris and her ethnicity or her gender have nothing to do with this whatsoever.”

The warnings point to the new risks for Republicans in running against a Democrat who would become the first woman, first black woman and first person of South Asian descent to win the White House.

Mr Trump, in particular, has a history of attacks that could turn off key groups of swing voters, including suburban women, as well as voters of colour and younger people which his campaign has been courting.

The meeting came after some members and Mr Trump’s allies began to cast the Vice President, a former district attorney, attorney general and senator, as a “DEI” hire — a reference to diversity, equity and inclusion initiatives.

“Intellectually, just really kind of the bottom of the barrel,” Wyoming Representative Harriet Hageman said in a TV interview. “I think she was a DEI hire. And I think that that’s what we’re seeing and I just don’t think that they have anybody else.”

Since President Joe Biden announced he was exiting the campaign, Republicans have rolled out a long list of attack lines against Ms Harris, including trying to tie her to the most unpopular Biden administration policies and his handling of the economy and the Southern border.

Trump campaign officials and other Republicans have accused her of being complicit in a cover-up of Mr Biden’s health issues and they have been mining her record as a prosecutor in California as they try to paint her as soft on crime.

Mr Johnson said both Mr Trump and Ms Harris have records in White House policy and said voters can compare how families were doing under the Trump administration with how they are doing now under Mr Biden.

“She is the co-owner, co-author, co-conspirator in all the policies that got us into the mess,” Mr Johnson said.

Mr Hudson told members at the Tuesday meeting that the NRCC is focusing on how Ms Harris is even more progressive than Mr Biden and essentially “owns” all the administration’s policies, according to a person familiar with the conversation.

Senator Steve Daines, who chairs the National Republican Senatorial Committee, echoed that criticism, calling Harris “too liberal.”

“She’s not an Irish Catholic kid who grew up in Scranton. She’s a San Francisco liberal,” Mr Daines said.

Mr Trump offered a similar argument in a call with reporters Tuesday.

“She’s the same as Biden but much more radical. She’s a radical left person and this country doesn’t want a radical left person to destroy it. She’s far more radical than he is,” he said.

“So I think she should be easier than Biden because he was slightly more mainstream, but not much,” he added.

In an interview on Newsmax, the former president claimed Ms Harris “destroyed the city of San Francisco,” although she left her job as district attorney there in 2011, and called her “the worst at everything”.

“Kamala Harris is just as weak, failed and incompetent as Joe Biden — and she’s also dangerously liberal,” the Trump campaign said in a statement. “Not only does Kamala need to defend her support of Joe Biden’s failed agenda over the past four years, she also needs to answer for her own terrible weak-on-crime record in California.”