President Donald Trump and other prominent American political figures are heading to Arizona to speak at a memorial for Charlie Kirk, the 31-year-old conservative activist who was killed two weeks ago.

The event, organised by Turning Point USA (TPUSA), is on Sunday at State Farm Stadium in Glendale and could be attended by more than 100,000 people.

Heightened security is expected, including 'TSA-level screening', according to TPUSA.

Kirk, who co-founded Turning Point USA when he was 18, was shot at a speaking event on a Utah university campus on 10 September, reigniting concerns about political violence in the US.

A polarising figure, differing perspectives about his legacy and possible motives for the shooting have exacerbated deep divisions in the US.

In addition to Trump, those expected to speak at the service include Kirk's widow, Erika, who took over his role as TPUSA CEO; Vice President JD Vance; the president's eldest son, Donald Trump Jr; right-wing political commentator Tucker Carlson; and homeland security adviser Stephen Miller.

The memorial service has the same security designation as high-profile events such as the Super Bowl.

Doors open at 08:00 local time for a program starting at 11:00, with the dress code being 'Sunday best - red, white or blue'. The event will also be live-streamed.