'Things happen' - Trump defends Saudi crown prince over Khashoggi killing

US President Donald Trump said Saudi Crown Prince Mohammed bin Salman "knew nothing" about the 2018 killing of journalist Jamal Khashoggi, as he welcomed the kingdom's de facto ruler to the White House.

Trump's comments appeared to contradict a US intelligence assessment in 2021 which determined the crown prince had approved the operation that led to Khashoggi's death at the Saudi consulate in Istanbul in 2018.

The crown prince, who has denied any wrongdoing, said at the White House that Saudi Arabia "did all the right things" to investigate Khashoggi's death, which he called "painful".

It was his first US visit since the assassination, which sent shockwaves through the US-Saudi relationship.

In the Oval Office on Tuesday, Trump shot back at a reporter who asked a question about the killing.

"You're mentioning someone that was extremely controversial," the US president said.

"A lot of people didn't like that gentleman that you're talking about. Whether you like him or didn't like him, things happen."

"But he [the Crown Prince] knew nothing about it," Trump added. "You don't have to embarrass our guests."

The crown prince added that Saudi Arabia "did all the right steps" to investigate the murder, which he called "painful" and a "huge mistake".

A US intelligence report made public in 2021 - under President Joe Biden's administration - determined that the crown prince had approved of a plan to "capture or kill" Khashoggi in Istanbul. During his first administration, Trump White House officials declined to release the report.

While dozens of Saudi officials faced sanctions in the wake of the assassination, none directly targeted the crown prince.