Mr Trump stepped up his personal attacks on the vice-president during what was billed as a speech on immigration following Ms Harris’ trip to the US-Mexico border.
“Joe Biden has become mentally deficient. Kamala was born like this. And if you think about it, only a mentally retarded person could have allowed our country to get to this point,” he said.
Mr. Trump has previously claimed that Ms. Harris has “gone black” and he repeatedly calls her “stupid,” “weak,” “lazy” and “dumb as hell.”
With just over a month to go until the presidential election, allies have pushed him, publicly and privately, to instead talk about the economy, immigration and other topics.
“I think the best thing to do is say his policies are destroying the country and they’re crazy liberal,” South Carolina Sen. Lindsey Graham said on “State of the Union.” on CNN.
When asked whether he approved of Mr. Trump’s latest remarks, Republican Congressman Tom Emmer avoided the question during an interview on the television show This Week from the ABC channel.
“Kamala Harris is a bad choice for America,” said Mr. Emmer, who is helping Mr. Trump’s running mate, JD Vance, prepare for Tuesday’s vice-presidential debate.
“I think Kamala Harris is as bad, if not worse, than the administration we have witnessed over the last four years,” he added.
Pressed for a response, Mr. Emmer replied: “I think we should stick to the issues. Donald Trump fixed the problems once. They (the Democrats) broke them. He’s going to fix them again.”
Ms Harris has not commented on Mr Trump’s recent attacks. When asked about other comments, she said it was the “same old show.” “It’s the same cookbook we’ve been hearing for years, with no plan for how it would meet the needs of the American people.”
Last month, Mr Trump said he had “the right” to make personal attacks against Ms Harris.
“As far as personal attacks go, I am very angry with her because of what she has done to the country. I am very angry with him for using the justice system as a weapon against me and others. I think I have the right to personal attacks,” he said in a press conference.
