"Joe Biden became ment@lly impaired, Kamala Harris was born ment@lly disabled" Trump sl@ms Biden and Harris (video)

Donald Trump heightened his disparaging remarks about Vice President Kamala Harris at a rally on Saturday, September 28, claiming she was born "mentally impaired."

The former president made the false assertions to a room of supporters in Prairie du Chien, Wisconsin, seemingly as a way to undermine Harris's leadership on immigration.

"Joe Biden became mentally impaired. Kamala, was born that way," Trump said to the audience, who erupted into laughter. "She was born that way."

The former president continued: "And if you think about it, only a mentally disabled person could've allowed this to happen to our country. Anybody would know this."

Trump was referring to the influx of migrants who have come into the United States over the last year.

A pillar of Trump's campaign is blaming Harris for migrant crossings by claiming it was her responsibility as vice president to tackle the issue.

Multiple Biden administration officials have said that Harris was only tasked with understanding the root cause of mass migration in Central American countries and leading diplomatic efforts to reduce those causes.

Watch Trump speak in the video below.