Vice President JD Vance has advocated for a slowdown in legal immigration during a speaking appearance in Mississippi, saying: “We have to get the overall numbers way, way down".

Vance took questions from students at the University of Mississippi at an event organised by Turning Point USA, stepping into the role of debater that was so often performed by the organisation's slain founder, Charlie Kirk.

Vance said the optimal number of legal immigrants to admit is “far less than what we've been accepting," but he did not offer a firm number when pressed by a woman who questioned his stance.

He criticised former President Joe Biden's immigration policies, which he said allowed too many people into the country and threatened the social fabric of the United States.

“When something like that happens, you’ve got to allow your own society to cohere a little bit, to build a sense of common identity, for all the newcomers — the ones who are going to stay — to assimilate into American culture,” Vance said.

“Until you do that, you’ve got to be careful about any additional immigration, in my view.”

Vance was introduced by Kirk's widow, Erika Kirk, in one of her first public appearances since she took over her husband's role leading Turning Point.