Ryan Routh has been sentenced to life in prison for attempting to assassinate President Donald Trump on a Florida golf course in September of 2024.

Routh, 59, was found guilty last year of trying to kill Trump, then still a presidential candidate, at the Trump International Golf Club in West Palm Beach.

A US Secret Service agent in the area spotted a rifle barrel poking out of the bushes and fired at Routh, who then fled the scene. He was arrested nearby.

In a sentencing memorandum, Judge Aileen Cannon said Routh's crimes "undeniably warrant a life sentence".

"[H]e took steps over the course of months to assassinate a major Presidential candidate, demonstrated the will to kill anybody in the way, and has since expressed neither regret nor remorse to his victims," she wrote.

Routh's lawyer, Martin Ross, said they would be appealing the case.

Routh pleaded not guilty and elected to represent himself during the trial, which began on 8 September.

A native of North Carolina who lived in Hawaii prior to his arrest, Routh repeatedly acted erratically during the court proceedings, including challenging Trump to a game of golf and making references to Adolf Hitler and Russian President Vladimir Putin.

After a jury found him guilty, Routh attempted to stab himself in the neck with a pen before US marshals quickly escorted him out of the courtroom.

While Routh is not believed to have had a clear line of sight to Trump at any point during the incident, federal agents told jurors they later recovered a semiautomatic rifle with a scope and an extended magazine in the spot where he had been hiding.

Additionally, jurors were told that Routh left behind a list of places where Trump was likely to appear, as well as a note for a friend which described the incident as "an assassination attempt".

In his closing statement during the trial, Routh spoke in the third person and touched on a wide variety of unrelated topics, including US history, the Russia-Ukraine war and his intention to buy a boat - prompting the judge to repeatedly interrupt him and send the jury away.

The lead prosecutor in the case, John Shipley, said that a "mountain of evidence" was presented which points to "how close he got to actually pulling this off".

The incident in Florida was the second attempt on Trump's life in 2024, after a gunman opened fire at a campaign rally in Butler, Pennsylvania, in July.

That shooting left one person dead and several wounded, including Trump.

The shooter, later identified as 20-year-old Thomas Crooks, was killed by officers at the scene.