Washington: In a solemn ceremony at the Pentagon marking the anniversary of the 9/11 attacks, US President Donald Trump announced that he will posthumously award conservative activist Charlie Kirk the Presidential Medal of Freedom, the highest civilian honour in the United States.

Trump paid tribute to Kirk as "a giant of his generation, a champion of liberty, and an inspiration to millions." He expressed deep sorrow over Kirk's assassination, which occurred just the day before at Utah Valley University, where Kirk was shot while addressing students.

"Before we begin, let me convey the horror and sorrow that many Americans are experiencing over the brutal murder of Charlie Kirk," Trump said. He extended condolences to Kirk’s wife, Erika, and their children, calling them "truly wonderful people." Trump also emphasised that Kirk’s voice and bravery, especially among young people, "will endure."

While the date for the award ceremony has not been finalised, Trump assured attendees that it would draw a "very, very large" crowd.

At 31, Kirk was a prominent conservative figure, co-founding the influential organisation Turning Point USA, which focused on engaging young conservatives on college and high school campuses. He was also a close ally of Trump and influential in conservative political circles.